ULTIMATE EFFECTS OF INANITION ON SIZE 113 



There is also unquestionably a difference in the effect of under- 

 feeding upon the ultimate growth of the body, depending upon 

 the severity of the inanition. As is well known, short periods of 

 inanition, even sufficiently severe to repress growth temporarily, 

 do not prevent the attainment of full adult size on subsequent 

 refeeding (Hatai, '07; Stewart, '16). The favorable results ob- 

 tained by Osborne and Mendel ('14, '15, '17) upon refeeding 

 after longer periods of inanition may be due in part to the fact 

 that in most cases their rats were not only older at the beginning 

 of the experiment, but were allowed to increase during the ex- 

 periment to a body weight considerably greater. That is, the 

 inanition was somewhat less severe than in our present series. 

 This perhaps also accounts for the fact that Osborne, Mendel 

 and Ferry ('17) found no decrease of reproductive capacity in 

 their female rats when amply refed after an extensive earlier 

 period of stunting. 



It should be emphasized that the present experiments repre- 

 sent very extreme degrees of underfeeding, at which even with 

 the greatest care many of the rats perish from inanition. Thus 

 the rats underfed from birth so as to restrict their body weight 

 to 15 or 16 grams at ten weeks would be roughly comparable to 

 children about twelve years of age so stunted by underfeeding 

 from birth as to reach a body weight of about 20 pounds, nor- 

 mally reached at one year. Similarly, a rat underfed from three 

 weeks to nearly a year (340 days) of age at about 60 grams body 

 weight would correspond roughly to a human of adult age dwarfed 

 by underfeeding from infancy so that the body weight would not 

 exceed that of a normal child below the age of puberty. 



Finally, there is doubtless a difference in the effect according 

 to the character of the inanition, particularly in inanition due to 

 qualitative deficiencies in the diet. Aron ('14) found that a 

 protein-poor diet appeared to affect more unfavorably the sub- 

 sequent growth of rats upon later refeeding than did a corre- 

 sponding degree of underfeeding with restricted amounts of a 

 normal diet. On the contrary, as previously mentioned, Os- 

 borne and Mendel ('14, '15) obtained complete recovery of body 

 weight upon proper refeeding of albino rats in which growth had 



