EFFECTS ON THE THYMUS 299 



'20a, '21) in pigeons and monkeys; by Emmett and Allen ('20) in rats; by 

 Cramer, Drew and Mottram ('21, '21a) in mice and rats; and by Findlay ('21) 

 and Korenchevsky ('23a) in pigeons and fowls. Findlay found total disappear- 

 ance of the thymus in the rice-fed as well as the starved animals (Table 13). 

 Lopez-Lomba ('23) noted a transient hypertrophy in the second period (9th 

 to 14th days), preceding the final atrophy of the thymus in adult pigeons on 

 vitamin-free diet. 



It may be noted, however, that during beriberi there is usually a general 

 emaciation, with marked loss in body weight, which might account for the 

 thymic atrophy, independent of any specific effect of the vitamin deficiency. 

 Thus Williams and Crowell ('15) concluded: "The experimental evidence 

 indicates that there is no apparent fundamental connection between beriberi 

 and the atrophy of the thymus; when the latter occurs in birds fed on polished 

 rice, as it frequently does, it is due to some other cause." On the other hand, 

 the atrophy of the thymus in beriberi is in agreement with the doctrine of 

 Cramer, Drew and Mottram ('21, '21a), according to which a deficiency of 

 vitamin B causes a specific atrophy of lymphoid tissue throughout the body. 



In scurvy, but few data on the thymus are available, according to Hess 

 ('20). Jacobsthal ('00) in a case of infantile scurvy found no apparent gross or 

 histological changes in the structure of the thymus. Bierich ('19) mentioned 

 an apparent enlargement of the thymus in 1 out of 8 (adult) cases. Aschoff 

 and Koch ('19) noted no abnormalities of the thymus in adult scurvy. 



During thirst (aqueous inanition), Falck and Scheffer ('54) observed an 

 apparent loss of 63 per cent in the thymus of a dog on dry diet, with loss of 

 20 per cent in body weight. In adult albino rats on acute thirst experiments, 

 Kudo ('21) found an apparent loss of 78 per cent in the thymus weight; while in 

 the chronic thirst series the loss averaged 90 per cent (Table 9). In similar 

 experiments on young albino rats, held at constant body weight by a relatively 

 dry diet, Kudo ('21a) found a loss of 68.9-91.3 per cent in the weight of the 

 thymus in the various test groups, being relatively greater than the loss in 

 any other organ (Table 10). 



