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MATSUZIRO TAKENOUCHI 



Percentage of the observed weight of the thymus compared with the weight calculated 

 on the body weight and on the age of the test and control animals. 

 * Average values 



thymus gland of the test rats, which might have been modified 

 in some way or other by the injected antithymus serum, do not 

 differ in weight from the glands of the controls. This is shown 

 in table 5. 



Similar studies made on the weight of other organs of the rats 

 do not indicate any specific action of the antithymus serum. 



Though I did not attempt to measure the long bones, inspec- 

 tion indicates that there is no distinct difference in the growth 

 of the bones between the rats injected with the antithymus 

 serum and the controls — a statement which is supported by the 

 relation of the body weight to the body length. 



Thus far we conclude that in growth in body weight, in the 

 weight of the thymus, and in the body and tail length, the test 

 and control animals do not show distinct differences from each 

 other. We have not observed any particular anaphylactic 

 symptoms in our animals, such as have been described by 

 Shimizu in his experiments with dogs, after the injection of the 

 antithymus serum; and in general are unable to see any specific 

 action of the anti-thymus serum in vivo, so far as the results of 

 macroscopical examination are concerned. 



/. Histological examination of the thymus glands of test and control 



rats 



After weighing, all the organs were fixed in Bouin's solution. 

 The upper portion of both lobes of the thymus of each rat was 

 used for serial paraffin sections which were stained with haema- 

 toxylin and eosin. 



