Studies on the Endoci-ine Glands 

 Tahi.e IV. 



277 



From May 12 to 18, groups A and B were fed with parathyroid ; from May 26 to 

 June 5, with fresh sheep-thyroid. 



It would appear from this table that there is no distinct difference in 

 the sexes in the effect on body-weight produced by thyroid feeding. 



Feeding with Thyroid for Varying Periods. 



In the following experiments 4 grm. of mixed fresh sheep-thyroid per 

 rat per diem was added to the food. 



(a) Male Rat (No. 7). Weight 220 grm. — In this animal a single dose 

 of the sheep-thyroid was given with the food at 9 a.m. on June 10. Sub- 

 sequently it was allowed an unlimited amount of rusk paste. Exactly 

 twenty-four hours after taking the thyroid the animal was killed. No 

 special symptoms observable. 



(b) Male Rat (No. 8). Weight 230 grm.— Fed with addition of 

 4 grm. fresh thyroid to food during two days (June 10 and 11). Killed 

 on June 12. No symptoms observable. 



(c) Male Rat (No. 9). Weight 230 grm.— Fed with addition of 

 4 grm. fresh sheep-thyroid during three days (June 10 to 12). On 

 June 12 slight diarrhoea observable, and the appetite had begun to 

 decrease. Killed on June 13. 



(d) Male Rats (Nos. 10, 11, 12, 13). Weights 220 grm., 210 grm., 

 225 grm., and 105 grm. respectively. — Fed during four days (June 

 10 to 13) with addition of sheep-thyroid. 



(e) Male Rats (Nos. 14 and 15). Weights 180 grm. and 210 grm. 

 respectively. — These rats were fed from June 10 on a diet containing 

 fresh sheep-thyroid. 



No. 10. — Began to have diarrhoea on June 12, and showed diminu- 

 tion of appetite. Killed on June 14. It had lost 15 grm. in weight. 



No. 11. — No special symptoms observed. On June 13 it had 

 lost 10 grm. in weight. Killed after one day's intermission of feeding. 



