292 Kojima 



healed ; there was some loss in weight, but only quite small. On the 

 twentieth day after the commencement of thyroid feeding one of the 

 animals of group A (No. 47, see Table XIV.) ceased to take food and had 

 considerable diarrhcea : it was therefore killed. The condition of the other 

 rat of group A was improving, the appetite gradually increasing and the 

 loss of weight being but slight. This animal was killed twenty-nine days 

 after the commencement of the feeding. The animals belonging to group B 

 remained well during the first week of the feeding, but later they gradually 

 became less active and their appetite appeared to be affected, the weights 

 becoming reduced. From June 16 onwards (twenty-one days) they were 

 for the most part lying prone on the floor of the cage. The rats forming 

 group B (Nos. 49 and 50) were killed on the twenty-seventh and twenty- 

 eighth days respectively (June 21 and 22). 



The rats belonging to groups A' and B' remained throughout perfectly 

 well, A positive iodine test was obtained throughout the whole experiment 

 in the urine of groups A and B (thyroid-fed). In groups A' and B' (without 

 thyroid) the test always proved negative. 



Those forming group A' (Xos. 51 and 52) were killed on June 23, and 

 one of the rats belonging to group B' (No. 54) was killed on June 18. 

 The other rat of group B' (No. 53) was not killed. 



Post-mortem. Group A. — In rat No. 47 (killed June 14) the stomach 

 is contracted and contains only mucus. Both the small and large intestines 

 are congested. The pancreas is pink in colour. The contents of the large 

 intestine are watery. In rat No. 48 nothing was noticeable. 



Group B. — In rats Nos. 49 and 50 the pancreas is fairly large and of 

 a reddish-pink colour. 



Microscopic Examination of the Pancreas. Rat No. 47 

 (thyroid feeding for twenty days, death from diarrhcea). — 

 The alveoli and their cells are generall}^ small. The nuclei vary 

 from 3/x to 9/x ; most of them are comparatively large, and contain 

 abundant coarse chromatin granules and enlaroed nucleoli staininof 



o o o 



red by Mallory. Fully formed zymogen granules are only to be seen 

 in a few of the alveoli (especially those near the islets). The granules 

 in the rest of the alveoli are shown by Muir's method, but are not 

 stained red by Mallory ; they are scattered through the cytoplasm, 

 and are not as usual confined to the inner zone. They perhaps repre- 

 sent a pro-zymogen. There are no mitoses to be seen. Some of the 

 cells contain vacuoles. 



Rat No. 48 (thyroid feeding for twenty-nine days). — 

 Although a few of the alveoli are large, most are small ; this applies 

 also to their constituent cells. The nuclei vary in diameter from 

 3'7/>t to 9,u. The larger ones contain large nucleoli stained red by 

 Mallory. There are no mitoses to be seen. Zymogen granules are 

 relatively scanty, but form a distinct mass in the cells, many of 

 which are vacuolated. 



Rats Nos. 49 and 50 (thyroid feeding for twenty-seven 

 and twenty-eight days). — The description of the pancreas which 



