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An AddressON

SOME PROBLEMS ARISING FROM THEVARIATIONS IN THE DEVELOPMENTOF THE SKULL AND THE BRAIN.

Delivered before the Anthropological Section of the BritishAssociation for the Advancement of Science at

Southport in September, 1903,

BY JOHNSON SYMINGTON, M.D. EDIN.,F.R.S.,

PRESIDENT OF THE SECTION; PROFESSOR OF ANATOMY AT, ANDREGISTRAR OF, QUEEN’S COLLEGE, BELFAST.

LADIES AND GENTLEMEN,-It is now nearly 20 yearssince anthropology attained to the dignity of being awardeda special and independent section in this Associationand I believe it is generally admitted that during this

period the valuable nature of many of the contributions,the vigour of the discussions, and the large attendance

of members have amply justified the establishment andcontinued existence of this section. While the multi-

farious and diverse nature of the subjects which are

grouped under the term ’’anthropology" gives a varietyand a breadth to our proceedings which are very re-

freshing in this age of minute specialism, I feel that itadds very considerably to the difficulty of selecting a subjectfor a presidential address which will prove of generalinterest. A survey of the recent advances in our knowledgeof the many important questions which come within thescope of this section would cover too wide a field for thetime at my disposal, while a critical examination of thevarious problems that still await solution might expose meto the temptation of pronouncing opinions on subjectsregarding which I could not speak with any real knowledgeor experience. To avoid such risks I have decided to limit imy remarks to a subject which comes within the range of myown special studies and to invite your attention to a con-sideration of some problems arising from the variations inthe development of the skull and the brain.

Since the institution of this section the development,growth, and racial peculiarities of both the skull and thebrain, and the relation of these two organs to each otherhave attracted an ever-increasing amount of attention. Theintroduction of new and improved methods for the study ofthe structure of the brain and the activity of an able band ofexperimentalists have revolutionised our knowledge of the

anatomy and physiology of the higher nerve centres. Thevalue of the results thus obtained is greatly enhanced bythe consciousness that they bear the promise of still greateradvances in the near future. If the results obtained by thecraniologist have been less marked, this arises mainly fromthe nature of the subject, and is certainly not due to anylack of energy on their part. Our craniological collectionsare continually increasing and the various prehistoric skull-caps from the Neanderthal to the Trinil still form the basisof interesting and valuable memoirs. While the additions toour general knowledge of cerebral anatomy and physiologyhave been so striking those aspects of these subjectswhich are of special anthropological interest have madecomparatively slight progress and cannot compare inextent and importance with the advances based upona study of fossil and recent crania. These facts admitof a ready explanation. Brains of anthropologicalinterest are usually difficult to procure and to keep, and

require the use of special and complicated methods for theirsatisfactory examination, while skulls of the leading racesof mankind are readily collected, preserved, and studied.Hence it follows that the crania in our anthropologicalcollections are as numerous, well preserved, and varied asthe brains are few in number and defective, both in theirstate of preservation and representative character. It mayreasonably be anticipated that improved methods of preserva-tion and the growing recognition on the part of anthropo-logists, museum curators, and collectors of the importanceof a study of the brain itself will to some extent at least

remedy these defects ; but so far as prehistoric man is con-cerned, we can never hope to have any direct evidenee ofthe condition of his higher nerve centres, and must dependfor an estimate of his cerebral development upon those moreor less perfect skulls which fortunately have resisted for somany ages the corroding hand of time.

I presume we will all admit that the main value of a goodcollection of human skulls depends upon the light whichthey can be made to throw upon the relative development ofthe brains of different races. Such collections possess few,if any, brains taken from these or corresponding skull!’, andwe are thus dependent upon the study of the skulls alone foran estimate of brain development.Vigorous attacks have not infrequently been made upon

the craniometric systems at present in general use, and theelaborate tables, compiled with so much trouble, giving thecircumference, diameters, and corresponding indices ofvarious parts of the skull are held to afford but littleinformation as to the real nature of skull variations, howeveruseful they may be for purposes of classification. While byno means prepared to express entire agreement with thesecritics, I must admit that craniologists as a whole have con-centrated their attention mainly on the external contour ofthe skull and have paid comparatively little attention to theform of the cranial cavity. The outer surface of the craniumpresents features which are due to other factors than braindevelopment, and an examination of the cranial cavity notonly gives us important information as to brain form butby affording a comparison between the external and internalsurfaces of the cranial wall it gives a valuable clue to thereal significance of the external configuration. Beyonddetermining its capacity we can do but little towards anexact investigation of the cranial cavity without making asection of the skull. 40 years ago Professor Huxley, in hiswork "On the Evidence of Man’s Place in Nature," showedthe importance of a comparison of the basal with the vaultedportion of the skull and maintained that until it shouldbecome " an opprobrium to an ethnological collection topossess a single skull which is not bisected longitudinally "there would be "no safe basis for that ethnologicalcraniology which aspires to give the anatomical characters ofthe crania of the different races of mankind." ProfessorJ. Cleland and Sir William Turner have abo insisted uponthis method of examination, and only two years ago Pro-fessor D. J. Cunningham, in his presidential address tothis section quoted with approval the forcible language ofHuxley. The curators of craniological collections appear,however, to possess an invincible objection to any such treat-ment of the specimens under their care. Even in theHunterian Museum in London, where Huxley himself workedat this subject, among several thousands of skulls scarcelyany have been bisected longitudinally or had the cranialcavity exposed by a section in any other direction. Themethod advocated so strongly by Huxley is not only essentialto a thorough study of the relations of the basi-cranial axisto the vault of the cranium and to the facial portion of theskull, but also permits of casts being taken of the cranialcavity, a procedure which, I would venture to suggest, hasbeen too much neglected by craniologists.Every student of anatomy is familiar with the finger-like

depressions on the inner surface of the cranial wall whichare described as the impress of the cerebral convolutions,but their exact distribution and the degree to which they aredeveloped according to age, sex, race, &c., still remain to bedetermined definitely. Indeed, there appears to be a con-siderable difference of opinion as to the degree of approxi-mation of the outer surface of the brain to the inner surfaceof the cranial wall. Thus the brain is frequently describedas lying upon a water bed or as swimming in the cerebro-spinal fluid, while Hyrtl speaks of this fluid as a "liga-mentum suspensorium " for the brain. Such descriptions aremisleading when applied to the relation of the cerebral con-volutions to the skull. There are, it is true, certain parts ofthe brain which are surrounded and separated from the skullby a considerable amount of fluid. These, however, are

mainly the lower portions, such as the medulla oblongataand pons Varolii, which may be regarded as prolongations ofthe spinal cord into the cranial cavity. As they contain thecentres controlling the action of the circulatory and respira-tory organs they are the most vital parts of the centralnervous system and hence need special protection. Theyare not, however, concerned with the regulation of com-

plicated voluntary movements, the reception and storage ofsensory impressions from lower centres, and the activity of

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the various mental processes. These functions we must asso-ciate with the higher parts of the brain and especially withthe convolutions of the cerebral hemispheres.

If a cast be taken of the cranial cavity and compared withthe brain which had previously been carefully hardened insitu before removal, it will be found that the cast not onlycorresponds in its general form to that of the brain, butshows a considerable number of the cerebral fissures andconvolutions. This moulding of the inner surface of the skullto the adjacent portions of the cerebral hemispheres is

usually much more marked at the base and sides than overthe vault. Since the specific gravity of the brain tissue ishigher than that of the cerebro-spinal fluid, the cerebrumtends to sink towards the base and the fluid to accumulateover the vault; hence, probably, these differences admit ofa simple mechanical explanation. Except under abnormalconditions, the amount of cerebro-spinal fluid between theskull and the cerebral convolutions is so small that from acast of the cranial cavity we can obtain not only a goodpicture of the general shape and size of the higher parts ofthe brain but also various details as to the convolutionarypattern. This method has been applied with marked successto the determination of the characters of the brain in variousfossil lemurs by Dr. Forsyth-Major and Professor R. Burck-hardt, and Professor Gustav Schwalbe has made a large seriesof such casts from his craniological collection in Strassburg.The interesting observations by Schwalbe 1 on the arrange-ment of the " impressiones digitatse " and " juga cerebralia," "and their relation to the cerebral convolutions in man, theapes, and various other mammals, have directed specialattention to a very interesting field of inquiry. As is wellknown the marked prominence at the base of the humanskull, separating the anterior from the middle fossa, fits intothe deep cleft between the frontal and temporal lobes of thebrain, and Schwalbe has shown that this ridge is continued-of course, in a much less marked form-along the innersurface of the lateral wall of the skull, so that a cast of thecranial cavity presents a shallow but easily recognised groovecorresponding to the portion of the Sylvian fissure of thebrain separating the frontal and parietal lobes from the

temporal lobe. Further, there is a distinct depression for thelodgment of the inferior frontal convolution and a cast ofthe middle cranial fossa shows the three external temporalconvolutions.We must now turn to the consideration of the relations of

the outer surface of the cranium to its inner surface and tothe brain. This question has engaged the attention of

experts as well as the " man in the street " since the time ofGall and Spurzheim and one might naturally suppose thatthe last word had been said on the subject. This, however,is far from being the case. All anatomists are agreed thatthe essential function of the cranium is to form a box forthe support and protection of the brain, and it is generallyconceded that during the processes of development andgrowth the form of the cranium is modified in response tothe stimulus transmitted to it by the brain. In fact it isbrain growth that determines the form of the cranium andnot the skull that moulds the brain into shape. This belief,however, need not be accepted without some reservations.Even the brain may be conceived as being influenced by itsimmediate environment. There are probably periods of

development when the form of the brain is modified by theresistance offered by its coverings and there are certainlystages when the brain does not fully occupy the cranialcavity.At an early period in the phylogeny of the vertebrate skull

the structure of the greater part of the cranial wall changesfrom membranous tissue into cartilage, the portion persistingas membrane being situated near the median dorsal line. Inthe higher vertebrates the rapid and early expansion of thedorsal part of the fore-brain is so marked that the cartilagi-nous growth fails to keep pace with it, and more and moreof the dorsal wall of the cranium remains membranous, andsubsequently ossifies to form membrane bones. Cartilage,though constituting a firmer support to the brain than mem-brane, does not possess the same capacity of rapid growthand expansion. The head of a young child is relativelylarge, and its skull is distinguished from that of an adult bythe small size of the cartilaginous base of the cranium ascompared with the membranous vault. The appearance oftop-heaviness in the young skull is gradually obliterated as

1 Ueber die Beziehungen zwischen Innenform und Aussenform desSchädels, Deutsches Archiv für Klinische Medicin, 1902.

age advances by the cartilage continuing slowly to grow afterthe vault has practically ceased to enlarge. These changesin the shape of the cranium are associated with corre-

sponding alterations in that of the brain and it appears tome that we have here an illustration of how the conditions ofskull growth may modify the general form of the brain.Whatever may be the precise influences that determine

skull and brain growth, there can be no doubt but thatwithin certain limits the external form of the cranium servesas a reliable guide to the shape of the brain. Statementssuch as those by Dr. J. Deniker "that the inequalities ofthe external table of the cranial walls have no relation what-ever with the irregularities of the inner table and still lesshave anything in common with the configuration of thevarious parts of the brain," are of too general and sweepinga character. Indeed, various observers have drawn attentionto the fact that in certain regions the outer surface of theskull possesses elevations and depressions which closelycorrespond to definite fissures and convolutions of thebrain. Many years ago Sir William Turner, who wasa pioneer in cranio-cerebral topography, found thatthe prominence on the outer surface of the parietalbone, known to anatomists as the parietal eminence,was situated directly superficial to a convolution of the

parietal lobe of the brain, which he consequently very appro-priately named the convolution of the parietal eminence."Quite recently Professor Schwalbe has shown that the

position of the third or inferior frontal convolution is indi-cated by a prominence on the surface of the cranium in theanterior part of the temple. This area of the brain is of

special interest to all students of cerebral anatomy and phy-siology, since it was the discovery by the illustrious Frenchanthropologist and physician, M. Broca, that the left inferiorfrontal convolution was the centre for speech, that laid thescientific foundation of our present knowledge of localisationof function in the cerebral cortex. This convolution is wellknown to be much more highly developed in man than inthe anthropoid apes and the presence of a human cranialspeech-bump is usually easily demonstrated. The facultyof speech, however, is such a complicated cerebral functionthat I would warn the I I new " phrenologist to be cautious inestimating the loquacity of his friends by the degree ofprominence of this part of the skull, more particularly asthere are other and more reliable methods of observation bywhich he can estimate this capacity.

In addition to the prominences on the outer surface of thecranium, corresponding to the convolutions of the parietaleminence and the left inferior frontal convolution, themajority of skulls possess a shallow groove marking theposition of the Sylvian point and the course of the horizontallimb of the Sylvian fissure. Below these two other shallowoblique grooves indicate the line of the cerebral fissureswhich divide the outer surface of the temporal lobe into itsthree convolutions, termed superior, middle, and inferior.Most of these cranial surface markings are partially obscuredin the living body by the temporal muscle, but they are ofinterest as showing that in certain places there is a closecorrespondence in form between the external surface of thebrain and that of the skull. There are, however, distinctlimitations in the degree to which the various cerebralfissures and convolutions impress the inner surface of thecranial wall or are represented by inequalities on its outeraspect. Thus over the vault of the cranium the position ofthe fissure of Rolando and the shape of the cerebral convolu-tions in the so-called motor area, which lie in relation to thisfissure, cannot usually be detected from a cast of the cranialcavity and are not indicated by depressions or elevations onthe surface of the skull, so that surgeons in planning theseats of operations necessary to expose the various motorcentres have to rely mainly upon certain linear and angularmeasurements made from points frequently remote fromthese centres.The cranium is not merely a box developed for the support

and protection of the brain, and more or less accuratelymoulded in conformity with the growth of this organ. Itsantero-lateral portions afford attachments to the muscles ofmastication and support the jaws and teeth, while its posteriorpart is liable to vary according to the degree of developmentof the muscles of the nape of the neck. Next to the brainthe most important factor in determining cranial form is thecondition of the organs of mastication-the muscles, the jaws,and the teeth. There is strong evidence in favour of the

2 The Races of Man, p. 53.

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view that the evolution of man from microcephaly to

macrocephaly has been associated with the passage from amacrodontic to a microdontic condition. The modificationsin the form of the cranium due to the influence of the organsof mastication have been exerted almost entirely upon itsexternal table ; hence external measurements of the cranium,as guides to the shape of the cranial cavity and indications ofbrain development, while fairly reliable in the higher races,become less and less so as we examine the skulls of thelower races, of prehistoric man, and of the anthropoid apes.One of the most important measurements of the cranium is

that which determines the relation between its length andbreadth and thus divides skulls into long or short, togetherwith an intermediate group neither distinctly dolichocephalicnor brachycephalic. These measurements are expressed byan index in which the length is taken as 100. If the pro-portion of breadth to length is 80 or upwards, the skull isbrachycephalic ; if between 75 and 80, mesaticephalic ; andbelow 75, dolichocephalic. Such a measurement is not so

simple a matter as it might appear at first sight and cranio-logists may themselves be classified into groups accordingas they have selected the nasion, or depression at the root ofthe nose, the glabella, or prominence above this depression,and the ophryon, a spot just above this prominence, as theanterior point from which to measure the length. In a

young child this measurement would practically be the samewhichever of these three points was chosen, and each pointwould be about the same distance from the brain. With theappearance of the teeth of the second dentition and theenlargement of the jaws the frontal bone in the region of theeyebrows and just above the root of the nose thickens andits outer table bulges forwards so that it is now no longerparallel with the inner table. Between these tables aircavities gradually extend from the nose, forming the frontalsinuses. Although the existence and significance of thesespaces and their influence on the prominence of the eyebrowswere the subject of a fierce controversy more than half acentury ago between the phrenologists and their opponentsit is only recently that their variations have been carefullyinvestigated.The frontal sinuses are usually supposed to vary according

to the degree of prominence of the glabella and the supra-orbital arches. This, however, is not the case. ThusSchwalbe3 has figured a skull in which the sinuses do notproject as high as the top of the glabella and supra-orbitalprominences and another in which they extend considerablyabove these projections. Further, Dr. A. Logan Turner,4 whohas made an extensive investigation into these cavities, hasshown that in the aboriginal Australian, in which this regionof the skull is unusually prominent, the frontal sinuses arefrequently either absent or rudimentary. The ophryon hasbeen selected by some craniologists as the anterior point fromwhich to measure the length of the skull under the impres-sion that the frontal sinuses do not usually reach above theglabella. Dr. Logan Turner, however, found that out of174 skulls in which the frontal sinuses were present in 130the sinuses extended above the ophryon. In 71 skulls thedepth of the sinus at the level of the ophryon varied fromtwo millimetres to 16 millimetres, the average being 5-2millimetres, while in the same series of skulls the depth atthe glabella varied from three millimetres to 18 millimetres,with an average depth of 8-5 millimetres. It thus appearsthat the selection of the ophryon in preference to theglabella, as giving a more accurate clue to the length of thebrain, is based upon erroneous assumptions, and that neitherpoint can be relied upon in the determination of the anteriorlimit of the cranial cavity. The difficulties of estimating theextent of the cranial cavity by external measurements andthe fallacies that may result from a reliance upon thismethod are especially marked in the case of the study of theprehistoric human calvaria, such as the Neanderthal and theTrinil and the skulls of the anthropoid apes.

Statistics are popularly supposed to be capable of provingalmost anything, and certainly if you allow craniologists toselect their own points from which to measure the length andbreadth of the cranium they will furnish you with tables ofmeasurements showing that one and the same skull is

dolichocephalic, mesaticephalic, and brachycephalic. Letus take as an illustration an extreme case, such as the skullof an adult male gorilla. Its glabella and supra-orbitalarches will be found to project forwards, its zygomatic arches

3 Studien über Pithecanthropus erectus, Zeitschrift für Morphologund Anthropologie. Band i., 1899.

4 The Accessory Sinuses of the Nose, 1901.

outwards, and its transverse occipital crests backwards, farbeyond the anterior, lateral, and posterior limits of thecranial cavity. These outgrowths are obviously correlatedwith the enormous development of the muscles of mastica-tion and those of the back of the neck. In a specimen inmy possession the greatest length of the cranium-i.e., fromglabella to external occipital protuberance-is 195 millimetresand the greatest breadth, taken between the outer surfacesof the zygomatic processes of the temporal bone, is 172 milli-metres, giving the marked brachycephalic index of 88’21.The zygomatic processes, however, may reasonably be

objected to as indicating the true breadth, and the side wallof the cranium just above the line where the root of thisprocess springs from the squamous portion of the temporalbone will certainly be much nearer the cranial cavity.Measured in this situation the breadth of the cranium is118 millimetres, which gives a length-breadth index 60’51and thus represents the skull as decidedly dolichocephalic.The transverse occipital crests and the point where thesemeet in the middle line to form the external occipital pro-tuberance are much more prominent in the male than in thefemale gorilla, and the estimate of the length of the craniumin this male gorilla may be reduced to 160 millimetres byselecting the base of the protuberance in place of its posteriorextremity as the posterior end measurement. This raises theindex to 73’75 and places the skull near the mesaticephalicgroup. At the anterior part of the skull the prominent glabellais separated from the inner table of the skull by large airsinuses, so that on a median section of the skull the distancefrom the glabella to the nearest part of the cranial cavity is36 millimetres. We have here, therefore, another outgrowthof the cranial wall which in an examination of the externalsurface of the skull obscures the extent of the cranial cavity.Accordingly, the glabella cannot be selected as the anteriorpoint from which to measure the length of the cranium andmust, like the zygomatic arches and occipital protuberance,be excluded from our calculations if we desire to determinea true length-breadth index. The difficulty, however, is toselect a definite point on the surface of the cranium torepresent its anterior end which will be free from the objec-tions justly urged against the glabella. Schwalbe suggeststhe hinder end of the supraglabellar fossa, which he statesoften corresponds to the beginning of a more or less dis-tinctly marked frontal crest. I have found this pointeither difficult to determine or too far back. Thus in mymale gorilla the posterior end of this fossa formed by themeeting of the two temporal ridges was 56 millimetresbehind the glabella and only 24 millimetres from the bregma,while in the female gorilla the temporal ridges do not meet,but there is a low median frontal ridge which may be con-sidered as bounding posteriorly the supraglabellar fossa.This point is 22 millimetres from the glabella and between50 and 60 millimetres in front of the bregma.

I would suggest a spot in the median line of the supra-glabellar fossa which is crossed by a transverse line unitingthe posterior borders of the external angular processes of thefrontal bone. I admit this plan is not free from objections,but it possesses the advantages of being available for bothmale and female skulls. In my male skull the selection ofthis point diminishes the length of the cranium by 25 milli-metres, thus reducing it to 137 millimetres. The breadth

being calculated at 114 millimetres, the index is 83’21, andhence distinctly brachycephalic. The length of the cranialcavity is 118 millimetres and the breadth 96 millimetres, andthe length-breadth index is thus the brachycephalic one of81-36.

I have given these somewhat detailed references to themeasurements of this gorilla’s skull because they show in avery clear and obvious manner that from an external exa-mination of the skull one might easily be misled as to thesize and form of the cranial cavity, and that, in order todetermine from external measurements the proportions ofthe cranial cavity, skull outgrowths due to other factors thanbrain growth must be rigorously excluded. Further, thesedetails will serve to emphasise the interesting fact that thegorilla’s skull is decidedly brachycephalic. This characteris by no means restricted to the gorilla, for it has beenclearly proved by Virchow, Schwalbe, and others that all theanthropoid apes are markedly round-headed. Ever since theintroduction by the illustrious Swedish anthropologist AndersRetzius of a classification of skulls according to the propor-tions between their length and breadth great attention hasbeen paid to this peculiarity in different races of mankind.It has been generally held that brachycephaly indicates a

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higher type of skull than dolichocephaly and that the Iincrease in the size of the brain in the higher races has t

tended to produce a brachycephalic skull. When the tcranial walls are subject to excessive internal pressure, as in : Fhydrocephalus, the skull tends to become distinctly brachy- t

cephalic, as a given extent of wall gives a greater internal Icavity in a spherical than an oval form. In estimating the (

value of this theory as to the evolutionary line upon which 1the skull has travelled it is obvious that the brachycephaliccharacter of the skulls of all the anthropoid apes is a fact (

which requires consideration.Although an adult male gorilla such as I have selected i

presents in an extreme degree outgrowths from the cranial ’.wall masking the true form of the cranial cavity, the same 1

condition, though to a less marked extent, is met with in thehuman subject. Further, it is interesting to note that thelength of the skull is more liable to be increased by suchgrowths than the breadth, since they occur especially overthe lower part of the forehead and to a less degree at theback of the skull, while the side walls of the cranium in theregion of its greatest breadth generally remain thin.Few if any fossils have attracted an equal amount of atten-

tion or given rise to such keen controversies as the Neander-thal and the Trinil skull-caps. According to some authorities

‘ both these skull-caps are undoubtedly human, while othershold that the Neanderthal belongs to an extinct species ofthe genus Homo, and the Trinil is the remains of an extinctgenus-Pithecanthropus erectu8 of Dubois-intermediatebetween man and the anthropoids. One of the most obviousand easily recognised peculiarities of the skull-caps is thevery marked prominence of the supra-orbital arches. Theglabella-occipital length of the Neanderthal is 204 milli-metres and the greatest transverse diameter, which is overthe parietal region, is 152 millimetres-an index of 74’ 51-while the much smaller Trinil calvaria, with a length of 181millimetres and a breadth of 130 millimetres, has an index of71’8. Both of these skulls are therefore slightly dolicho-cephalic.Schwalbe has corrected these figures by making reductions

in their lengths on account of the frontal "outworks," sothat he estimates the true length-breadth index of theNeanderthal as 80 and that of the Trinil as 75-5. Theseindices, thus raised about 5 per cent., are considered torepresent approximately the length-breadth index of thecranial cavity. A comparison of the external and internalmeasurements of many recent skulls with prominent glabellaewould, I suspect, show a greater difference than that calcu-lated by Schwalbe for the Neanderthal and Trinil specimens.In a male skull, probably an aboriginal Australian, with acranial capacity of 1227 cubic centimetres I found that theglabella-occipital length was 189 millimetres, and the trans-verse diameter at the parieto-squamous suture 127 milli-metres, which gives an index of 67’ 20 and makes the skulldecidedly dolichocephalic. The length of the cranial cavity,however, was 157 millimetres and the breadth 121 milli-metres (an index of 77’ 07 and a difference of nearly 10 percent.), so that while from external measurements theskull is distinctly dolichocephalic, the proportions of its

cavity are such that it is mesaticephalic. It is probable thatmany skulls owe their dolichocephalic reputation simply tothe prominence of the glabella and supra-orbital ridges. Anexcessive development of these structures is also liable togive the erroneous impression of a retreating forehead. Inthe Australian skull just mentioned the thickness of thecranial wall at the glabella was 22 millimetres ; from thislevel upwards it gradually thinned until 45 millimetres abovethe glabella it was only six millimetres thick. When thebisected skull was placed in the horizontal position theanterior surface of the frontal bone sloped from the glabellaupwards and distinctly backwards, while the posterior orcerebral surface was inclined upwards and forwards. In

fact, the cranial cavity in this region was separated from thelower part of the forehead by a wedge-shaped area havingits apex upwards and its base below at the glabella. The

cranial wall opposite the glabella is not appreciably thickerin the Neanderthal calvaria than in the Australian skull towhich I have already referred, and the form of the cranialcavity is not more masked by this prominence in theNeanderthal than in many of the existing races.Although the Neanderthal skull is by no means complete,

the base of the cranium and the face bones being absent,still those parts of the cranial wall are preserved that arespecially related to the portion of the brain which subservesall the higher mental processes. It includes the frontal,

parietal, and upper part of the occipital bones, with parts ofthe roof of the orbits in front and of the squamous division ofthe temporal bones at the sides. On its inner or cranialaspect there are markings by which the boundaries betweenthe cerebrum and the cerebellum can be determined. In a

profile view of such a specimen an inio-glabellar line can bedrawn which will correspond very closely to the lower

boundary of the cerebrum and indicate a horizontal planeabove which the vaulted portion of the skull must havecontained nearly the whole of the cerebrum.

’ Schwalbe has devised a series of measurements to illus-trate what he regards as essential differences between theNeanderthal skull-cap and the corresponding portion of thehuman skull. From the inio-glabellar line another is drawnat right angles to the highest part of the vault and by com-paring the length of these two lines we can determine thelength-height index. According to Schwalbe this is 40’ 4 inthe Neanderthal, while the minimum in the human skull is52. He further shows that the frontal portion of the vault,as represented by a glabella-bregmatic line, forms a smallerangle with the base or inio-glabellar line, and that a verticalline from the posterior end of the frontal bone (bregma) cutsthe inio-glabellar further back than in the human subject.Professor King of Galway attached special importance to theshape and proportions of the parietal bones and more par-ticularly to the fact that their mesial borders are shorterthan the lower or temporal, whereas the reverse is the casein recent man. This feature is obviously related to thedefective expansion of the Neanderthal vault and ProfessorSchwalbe also attributes considerable significance to thispeculiarity.

’

Another distinctive feature of the Neanderthal skull is therelation of the orbits to the cranial wall. Schwalbe showsthat its brain-case takes a much smaller share in the forma-tion of the roof of the orbit than it does in recent man, andProfessor King pointed out that a line from the anteriorinferior angle of the external orbital process of the frontalbone, drawn at right angles to the inio-glabellar line, passedin the Neanderthal in front of the cranial cavity, whereas inman such a line would have a considerable portion of thefrontal part of the brain-case anterior to it.From the combined results of these and other measure-

ments Schwalbe arrives at the very important and interestingconclusion that the Neanderthal skull possesses a number ofimportant peculiarities which differentiate it from the skullsof existing man and show an approximation towards those ofthe anthropoid apes. He maintains that in recognising withKing 6 and Oope the Neanderthal skull as belonging to adistinct species, Homo Neanderthalensis, he is only followingthe usual practice of zoologists and paleontologists by whomspecific characters are frequently founded upon much lessmarked differences. He maintains that as the Neanderthalskull stands in many of its characters nearer to the higheranthropoids than to recent man, if the Neanderthal type isto be included under the term Homo sapiens then this

species ought to be still more extended so as to embrace theanthropoids.

It is interesting to turn from a perusal of these opinions; recently advanced by Schwalbe to consider the grounds on which Huxley and Turner, about 40 years ago, opposed the. view, which was then being advocated, that the characters, of the Neanderthal skull were so distinct from those of anyL of the existing races as to justify the recognition of a new species of the genus Homo. Huxley, while admitting that; it was "the most pithecoid of human skulls," yet holds that it is by no means so isolated as it appears to be at first,! but forms in reality the extreme term of a series leading! gradually from it to the highest and best developed of6human crania." He states that "it is closely approached. by certain Australian skulls and even more nearly by thei skulls of certain ancient people who inhabited Denmarki during the stone period." Turner’s observations led him

to adopt a similar view to that advanced by Huxley. He compared the Neanderthal calvaria with savage and Britishr crania in the Anatomical Museum of the University of) Edinburgh and found amongst them specimens closelycorresponding to the Neanderthal type. While yielding to no one in my admiration for the

5 Ueber die specifischen Merkmale des Neanderthalschadels, Ver-handlungen der Anatomischen Gesellschaft in Bonn, 1901.

6 The Reputed Fossil Man of the Neanderthal, Journal of Science,1864.

7 The Genealogy of Man, The American Naturalist, vol. xxvii., 1893.8 The Fossil Skull Controversy, Journal of Science, 1864.

874

thoroughness and ability with which Schwalbe has con-ducted his elaborate and extensive investigations on this

question I must confess that, in my opinion, he has not suffi-ciently recognised the significance of the large cranial

capacity of the Neanderthal skull in determining the zoologi-cal position of its owner or made sufficient allowance for thegreat variations in form which skulls undoubtedly human Imay present. The length and breadth of the Neanderthalcalvaria are distinctly greater than in many living races andcompensate for its defect in height, so that it was capableof lodging a brain fully equal in volume to that of manyexisting savage races and at least double that of anyanthropoid ape.A number of the characters upon which Schwalbe relies in

differentiating the Neanderthal skull-cap are due to an appre-ciable extent to the great development of the glabella andsupra-orbital arches. Now these processes are well knownto present very striking variations in existing human races.They are usually supposed to be developed as buttresses forthe purpose of affording support to the large upper jaw andenable it to resist the pressure of the lower jaw due to thecontraction of the powerful muscles of mastication. These

processes, however, are usually feebly marked in the micro-cephalic, prognathous, and macrodont negro skull and maybe well developed in the macrocephalic and orthognathousskulls of some of the higher races. Indeed, their variationsare too great and their significance too obscure for them toform a basis for the creation of a new species of man. Both iHuxley and Turner have shown that the low vault of the iNeanderthal calvaria can be closely paralleled by specimens ’,of existing races.

If the characters of the Neanderthal calvaria are so dis-tinctive as to justify the recognition of a new species, a newgenus ought to be made for the Trinil skull-cap. In nearlyevery respect it is distinctly lower in type than the Neander- i

thal, and yet many of the anatomists who have expressed I

their opinion on the subject maintain that the Trinil specimenis distinctly human.

Important and interesting as are the facts which may beascertained from a study of a series of skulls regarding thesize and form of the brain, it is evident that there are

distinct limits to the knowledge to be obtained from thissource. Much additional information as to racial characterswould undoubtedly be gained had we collections of brainsat all corresponding in number and variety with the skullsin our museums. We know that as a rule the brains of theless civilised races are smaller and the convolutions andfissures simpler than those of the more cultured nations,beyond this but little more has been definitely determined.As the results of investigations in human and comparative

anatomy, physiology, and pathology, we know that definiteareas of the cerebral cortex are connected with the action ofdefinite groups of muscles and that the nervous impulsesstarting from the organs of smell, sight, hearing, andcommon sensibility reach defined cortical fields. Allthese, however, do not cover more than a third of theconvoluted surface of the brain, and the remaining two-thirds are still to a large extent a terra incognita so far astheir precise function is concerned. Is there a definitelocalisation of special mental qualities or moral tendenciesand if so where are they situated ? These are problems of ex-treme difficulty, but their interest and importance are difficultto exaggerate. In the solution of this problem anthro-

pologists are bound to take an active and important part.When they have collected information as to the relative

development of the various parts of the higher brain in allclasses of mankind with the same thoroughness with whichthey have investigated the racial peculiarities of the skullthe question will be within a measurable distance ofsolution.

TAVISTOCK HOSPITAL AND DISPENSARY.-A newwing to the Tavistock Hospital was formally opened byMr. W. Spear, M.P., on Sept. 16th, in the presence of a

large gathering. The cost of the building has been defrayedout of the invested funds of the institution, but the main-tenance will receive the benefit of a bequest of elm,500under the will -of the late Mr. J. H. Gill. The new winghas been erected on land given by the Duke of Bedford andcontains ten beds, a laundry, and nurses’ quarters. It is tobe known as the Gill wing. The Tavistock Hospital nowcontains 25 beds and last year 125 in-patients were admittedand 558 out-patients were treated.

A CASE PRESENTING SIGNS OF PUL-MONARY STENOSIS DURING LIFE,UNEXPLAINED BY THE NECROPSY,

WITH SOME REMARKS ONDIAGNOSIS.

BY W. L. ASCHERSON, M. B., B. C. CANTAB., M. R.C. P. LOND.,MEDICAL REGISTRAR, ST. GEORGE’S HOSPITAL.

A MAN, aged 28 years, was admitted into St. George’sHospital under the care of Sir Isambard Owen on

June 6th, 1903, complaining of indefinite nervous sym-ptoms. On admission he was found to be very weak

and somewhat delirious. The pulse was 84, of moderate

tension, with a thickened radial artery ; the tongue was moist,tremulous, and thickly coated ; diarrhoea was present,from seven to eight motions occurring in the 24 hours ; theurine, which was of specific gravity 1010, was loaded withalbumin. His mental state was not such as to permit ofreliance being placed in his history, but information obtainedfrom relatives pointed to an illness of some three weeks’duration, during which he had suddenly partially lost vision .

in the left eye. The movement of the chest was equalon both sides. The apex beat of the heart was found to bein the fifth left space one and a half inches outside theleft mid-clavicular line ; its impulse, thrusting in character,suggested hypertrophy. Praecordial dulness extendedtransversely from the right border of the sternum to withinone inch of the anterior axillary line ; vertically, it mergedabove into a dull area occupying the inner part of the uppertwo left spaces and involving the manubrium sterni. In thesecond left space, at a distance of about half an inch fromthe left sternal border, systolic pulsation was visible and onpalpation a long-sustained thrill was felt. On auscultationthe thrill was found to correspond with a long purringsystolic murmur leading up to an extraordinarily loud andabrupt second sound. A diastolic shock was also palpable.The murmur was pretty generally conducted over the

prascordium, right and left of the sternum, but diminishedimmediately in intensity on moving the stethoscope awayfrom the region above mentioned. Over the dull area in thefirst and second left spaces intense tubular breathing washeard, entirely different in character from the harsh breathingordinarily heard in this situation and strongly suggestive ofthe presence within the chest of some abnormal source ofconduction of the tracheal sounds to the surface, a sugges-tion which was emphasised by the discovery of tubular

breathing over the three upper dorsal spines, extendingrather further to the left than to the right. The air entry atboth bases was fair and equal on either side, nor was any-thing further abnormal to be detected in the lungs byphysical examination. The abdomen showed some tympanitesand was slightly tender.

It seemed difficult to make the various elements of thecase conform to the clinical picture of any one definitemorbid entity. The diarrhoea, albuminuaia, and mentalcondition were conformable to a diagnosis of ursemia super-vening in disease of the kidney but the signs in the chestwere baffling. The character and position of the murmurseemed to indicate stenosis of the pulmonary artery ; thearea of dulness and intense tracheal breathing pointed tomediastinal tumour of some sort as a possible cause of thestenosis. Other signs of aneurysm were not sufficientlymarked to be confirmative ; tracheal tugging was thought tobe present ; the pupils were dilated, and the left was a littlelarger than the right ; the radial pulses were equal ; the voicewas not abnormal. Examination of the larynx was notattempted in the condition in which the patient was. Therewas no definite sign of pressure in the left bronchus. Thearch of the aorta could not be felt on deep palpation inthe episternal notch nor was the pulsation in the necknoticeably forcible. The heart revealed no sign pointing tadisease of the aorta. On the other hand, there was no

special sign of growth, such as obstruction of the superiorvena cava. Some abnormal condition was certainly sus-pected within the mediastinum but exactly what was

not clear. The course of the man’s illness after admissionwas short. His delirium increased and he became restlessand noisy, sleeping but little during the night. On the next

day he had an attack of what seemed to be acute œdema