Studies on the Endocrine Glands 



293 



has been given for No. 48 appHes ^^enerally for Nos. 40 and 50 (con- 

 trol entire rats). The.se also show no mitoses. Zymogen granules 

 are, however, al)undunt in all the alveoli, and vacuoles of variable 

 size occur in many of the alveolar cells. 



Rats Xos. 51 and 52, 53 and 54, groups A' and B'. — These are 

 the animals which had received lean meat instead of thyroid, two 

 having been castrated and the other two being entire. The pancreas 

 in all exhibits the normal microscopic appearance, the alveoli and 

 the alveolar cells being of nearly equal .size throughout, and the 

 nuclei averaging about 5;x. Zymogen granules are also fairly plenti- 

 ful, and very few cells contain vacuoles. 



Table XIV. — Effect of Thyroid Feeding on Castrated Rats. 



Summary. — Castration appears neither to have any distinct effect 

 upon the structure of the pancreas nor to influence the effects of thyroid 

 feedincr. 



Does the Administration of Combinations of Iodine with Protein 



AFFECT THE PANCREAS IN THE SAME WAY AS ThYROID SuBSTANCE ? 



The administration by the mouth of a mixture (or combination) obtained 

 from Parke, Davis & Co., and termed by them " thyro-protein," and of 

 a substance obtained from Martindale termed " iodo-protein," was next 

 investigated. The 2-grain tablets of thyro-protein are stated to be 

 composed as to 2 per cent, of their weight of a concentrated substance 

 extracted from thyroid. Iodo-protein has the form of a brown powder 

 containing about 10 per cent, of iodine, and having a slight odour 

 of iodine. It is apparently an artificial compound. It is insoluble in 



