THE PKOTEIN METABOLISM OF MANKIND 95 



tinuously through countless generations, must eventually lead 

 to the evolution of a race whose individuals are relatively on a 

 lower scale of physical development than that of the better-fed 

 races of European countries. If, after the period of suckling 

 is over, Bengali children were given liberal quantities of the 

 materials on which growth depends, they might be expected to 

 make up the lost ground to some extent, although the general 

 opinion of animal breeders is against such a contention, it being 

 widely held amongst these classes that if a strong, well-developed 

 animal of whatever species is wanted, it must be well fed from 

 birth. As has been shown, however, the Bengali never receives 

 sufficient protein at any age to do much more than meet the 

 pressing requirements of ordinary wear and tear, so that the 

 excess of protein available for the growth and building up of 

 the nitrogenous tissues never reaches a high level. 



In accordance with this chronic state of more or less nitrogenous 

 starvation, we find the Bengali poor in physique, very poor in 

 muscular tissue, the body fat at a minimum, and the average 

 working man absolutely incapable of prolonged or sustained 

 muscular efforts. The average body weight of the Bengali is 

 50 kilos, that of the European 65 to 70 kilos. 



We may now turn from the consideration of the dietaries 

 themselves to the study of the effects of those dietaries, particu- 

 larly as regards their protein constituents. 



