ENDOCRINE FUNCTION OF THE THYMUS GLAND 313 



('11) used rabbits for immunization to obtain a thymotoxic 

 serum, with positive results when dog thymus extract was em- 

 ployed as the antigen. ''Weymersch ('08) sah nach Injektion 

 von thymotoxischen Serum eihe weitgehende Atrophie und 

 Sklerosierung der Thymusdriise, eine abnorme Verteilung der 

 Leucocyten und exzessive Wachstum der Thiere" (cited from 

 Shimizu's paper, p. 262). Ritchie ('08) obtained a serum from 

 ducks by injection of the thymus of guinea-pigs, but observed 

 no specific action of that serum, when injected, on the thymus 

 of guinea-pigs. He states, however, that in the presence of this 

 immune serum from ducks, guinea-pig complement becomes 

 fixed to the guinea-pig thymus, lymph glands, bone marrow, and 

 spleen. Ritchie used in his experiment a hemol3^tic system con- 

 sisting of ox blood and anti-ox rabbit serum. He concludes from 

 this experiment that the serum obtained from ducks which had 

 been treated with the thymus glands of guinea-pigs contained a 

 'leucophihc immune body,' and not a specific thymolytic one, 

 and that the structural changes in the thymus of the guinea-pigs 

 following the injection of the serum were due to its 'leiicolytic 

 action,' and are not specific. 



Moorhead ('05), however, found that the serum of rabbits 

 which had been injected with guinea-pig's thymus glands had 

 no recognizable leucolytic action, did not ''agglutinate emulsi- 

 fied thymus gland in vitro," and had no constant action upon 

 the animals into which it was injected. 



Recently Shimizu ('13) reports his success in obtaining a very 

 strong thymolytic serum, which he says resulted, after injection 

 in young dogs, in a marked retardation of bone growth, together 

 with a strong atrophy of the medullary portion of the thymus, 

 and a proliferation of connective tissue. These responses 

 occurred in two animals among fifteen so treated, while there 

 were in all the other individuals more or less pronounced toxic 

 symptoms corresponding to the so-called primary anaphylaxis. 

 In the summary of his paper he says : 



Bekanntlich ist die Veranderung der Thymus bei Inanition haupt- 

 sachlich die Involution der Rindensubstanz, und das Mark bleibt 

 dabei wohlbehalten. Thymusatrophie bei der Rontgendurchstrahlung 



