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to established doctors who can prove loss of netincome, and will therefore be of no avail to thenewcomer to practice. The eventual answer willprobably be found to lie in a graded capitation fee,allowing proportionately more for the first 1000(or other agreed figure) on a principal’s list of patients.This seemed to be within reach, and would have beenintroduced if money had been available to augmentthe practitioners’ pool. But even without suchaugmentation the Conference of Local MedicalCommittees must soon consider whether in equityit should not still propose modification of the dis-tribution scheme so as to alleviate the lot of thedoctors in areas where lists are small and static. Thenew grants should be a very present help, but theywill not in themselves banish that sense of hope-lessness and frustration felt by so many who findthemselves working quite as hard as before, and

usually harder, to earn an income which per-sistently remains below their needs. Such men andwomen can fairly expect that ways will be foundto pay them properly for their work. If thiswere done, hardship grants would not be needed,for real hardship would no longer exist.

Aureomycin and GrowthTHE borderland between bacteriology and nutrition

is attracting many investigators these days, and theirfindings seem likely to have valuable practical applica-tions in stock-breeding as well as in medicine. Last

year STOKSTAD and his co-workers 1 in New Yorkreported that the addition to the diet of a factorobtained from cultures of Streptomyces aureofaciens,the organism which produces Aureomycin,’ wouldenhance the growth of chicks receiving a feed withsoybean meal as the source of protein and an adequateamount of vitamin B12. The same effect was observedby others in young pigs 2 and young turkeys.3 Now,at the national meeting of the American ChemicalSociety in Philadelphia, STOKSTAD and JuKES havereported some important further work on this subject.The growth-promoting effect was observed with

whole cultures of the aureomycin-producing mould,with fractions that contained and others that didnot contain aureomycin, and, though less regularly,with crystalline aureomycin in very small quantities- 12 mg. of aureomycin in 1 lb. of food produceda well-marked response. The effect was quite distinctfrom that attributable to vitamin Bi2, which culturesof the mould contain. This was clearly establishedby including adequate amounts of vitamin B12 inthe experimental diets, and also by showing thataureomycin enhanced the growth of animals fed ondiets with fish meal as the source of protein and there-fore rich in "

animal-protein factor," with whichvitamin B12 seems to be identical. In seeking toexplain how aureomycin increased the growth of

young chickens, pigs, and turkeys, STOKSTAD andJUKES observed that the growth response was greatestwhen aureomycin was added to diets providingsuboptimal amounts of vitamin B,2. This led them to

1. Stokstad, E. L. R., Jukes, T. H., Pierce, J. V., Page, A. C. jun.,Franklin, A. L. J. biol. Chem. 1949, 180, 647.

2. Cunha, T. J., Buruside, J. E., Buschman, D. M., Glasscock, R. S.,Pearson, A. M., Shealey, A. L. Arch. Biochem. 1949, 23, 324.

3. McGinnis, J., Stephenson, E. L., Levadie, B. T., Carver, J. S.,Garibaldi, J. A., Ijichi, K., Snell, N. S., Lewis, J. C. Abstr.Amer. chem. Soc. September, 1949, p. 42.

think that aureomycin somehow reduced the animals’requirement for vitamin B12. Following up theobservation of MooxtE et al.,4 that succinylsulpha-thiazole hastened the growth of animals given a syn-thetic diet, STOKSTAD and JuKES confirmed that

succinylsulphathiazole also increased the growth ofchicks given one of their experimental diets, thoughthe response was less than with aureomycin. Byanalogy, therefore, STOKSTAD and JuKES argue thataureomycin may act not by supplying an unknownnutrient but by altering the intestinal microfloraso that a smaller amount of vitamin B12 has to besupplied in the food.The economic importance of this work is clear,

for in 3-4 weeks young, rapidly growing animalsreceiving a small quantity of aureomycin were in mostexperiments 25-50% heavier than those not givenaureomycin. The scientific implications are also

important. Nutrition is a meeting-ground of manyscientific disciplines, and this work is a challenge tothe inadequacy of our understanding of the roleof the intestinal microflora in nutrition. Here theproblem is to devise adequate methods of charac-terising the bacterial population of the intestinaltract, and so identifying the changes that resultfrom alterations in the diet. In this difficult task,as MASSON 5 and NASR 6 demonstrated to the Nutrition

Society at Aberdeen, there is much to be learntfrom the proper use of modern microscopical andhistochemical methods. BAKER has long insistedthat the application of such methods, and an intel-ligent interpretation of their results, is the most

helpful starting-point and an essential control for thecultural and biochemical studies necessary to completeour knowledge of the nutritional consequences of

changes in the intestinal microflora. At presentthese consequences seem more often to be vaguelypostulated than demonstrated.

Protomedicus AnglorumIF the preposterous Austrian title of protomedicus

were revived for England and Wales, the man withthe best claim to it would be, of course, a Scot.Sir WILSON JAMESON, chief medical officer to theMinistries of Health and Education, retired on May 11after ten years’ service covering the most profoundchanges in medical organisation that this countryhas seen. Happily, when he took office in November,1940, at the shortest notice, he had qualifications noteven exceeded by those of his first and most distin-guished forerunner, Sir JOHN SIMON. Well groundedin the practice of local public health through servicein four London boroughs, in his period as dean of theLondon School of Hygiene and Tropical Medicine andprofessor of public health in London University he hadbeen brought into personal touch with both theacademic and administrative sides of medicine to anextent hitherto unknown. Add to that a wide

experience as medical adviser to the Colonial Office(an experience by no means limited to a desk in

Whitehall) ; the co-authorship of the standard text-book on public health ; a gift for establishing har-4. Moore, P. R., Evenson, A., Luckey, T. D., McCoy, E., Elvehjem,

C. A., Hart, E. B. J. biol. Chem. 1946, 165, 437.5. Masson, Marjorie. Brit. J. Nutrition, 1950, 4. Proceedings of the

60th Scientific Meeting of the Nutrition Society (in the press).6. Nasr, Hamed. Ibid (in the press).7. Baker, F., Nasr, H. J. R. microscop. Soc. 1947, 67, 27.