314 MATSUZIRO TAKENOUCHI 



betrifft auch die Rinde. Die bei den Ernahrungsstorungen und akuten 

 Infektionskrankheiten der Sauglinge vorkommende Veranderung der 

 Thymus ist auch eine Rindenatrophie. Wie Hammer betont hat, 

 sieht man eigenthch nur die Rindenatrophie sowohl bei der Alters — ■, 

 als auch bei der durch Hunger, toxische Einfliisse etc. hervorgerufenen 



akzidentellen Involution Mein Thymolysin ruft haupt- 



sachlich deutliche Atrophie des Marks hervor, und die behandelte 

 Tiere zeigen dieselbe korperlichen und geistigen Entwicklungen, die 

 von den friiheren Autoren bei Thymektomie beobachtet worden sind. 



From the result of his experiments he concludes that the 

 medullary portion of the thymus has biologically a distinctly 

 different function from the cortical portion, and that the endo- 

 crine function of this gland with its influence upon the growth of 

 animals, must be ascribed to the medullary portion only. He 

 does not give definite proof for any endocrine function whatever 

 of the thymus, at least in his first paper,^ and he made his con- 

 clusion with the complete acceptance of the theory of the thy- 

 mus-skeleton relationship, which had already been firmly estab- 

 lished in the minds of many. 



As is easily imagined, it would be one of the best methods for 

 the study of the function of the thymus gland to destroy it alone 

 in vivo by some other than surgical means, for in.stance, by some 

 serological procedure, and observe the symptoms or pathological 

 alterations which might follow. 



Shimizu does not give any definite proof for the presence of his 

 thymolysin in vitro. Also he does not give any histological de- 

 scription of the lymphoid tissues of dogs injected with his thy- 

 molysin. This is important, because the cells which make up 

 the thymic tissue belong to the vascular system, according to 

 Danchakoff ('16), and therefore we might expect the lymphoid 

 tissues to respond in some way or other to the thymolysin. 



Originally I hoped to repeat in full Shimizu's experiments, 

 using albino rats instead of dogs, and thus to get further infor- 

 mation regarding the function of the thymus in the albino rat. 



^ It is said that Shimizu has published his second paper regarding the same 

 problem, and some other Japanese investigators have done work in Japan along 

 this line and published their results. We are, unfortunately, not able to obtain 

 these original reports in time, therefore this paper is written without the knowledge 

 of their publication. 



