INANITION OF THYROII) I.\ ]{ATS o07 



sludietl from those su})jec't('(l to acute inanition, and .S IVoin tliose 

 with ehroiiie inanition. 



The material was obtained at tlie autoi)sy held innnediately 

 after the animals wcM'e killed, and was fixed chiefly in Zenker's 

 fluid, 12 to 24 hours. In a few cases formalin or Flennning's 

 fluid w^as used, but the results w^ere less satisfactory. 



The glands were embedded in paraffin, and cut at 5 micra 

 (occasionally 7 to 10 micra) in thickness. In the great majority 

 of cases, the glands were cut and mounted in complete serial 

 sections. This was found to l)e important, not only to make 

 certain of including the parathyroids, but also because the struc- 

 ture frequently A'aries in different parts of the thyroid and para- 

 thyroid glands. 



The sections were stained in most cases with haemat()x\din and 

 eosin; in a few cases with iron-haematoxylin, safranin, Mallory's 

 anilin-blue connective tissue stain, etc. 



All of the drawings were made with a Zeiss 2 nnn. 1.30 N. A. 

 apochromatic objective and compensating ocular No. 6, with 

 the aid of a camera lucida. A wheel-micrometer eyepiece was 

 used for the measurements. It was the oiiginal intention to 

 measure systematically a large number of cells and nuclei in the 

 glands of the controls and of the animals subjected to inanition. 

 On account (^f the great irregularity in the size and shape of cells 

 and nuclei, however, it was found that the results, though of 

 limited value, could not be obtained with sufficient accuracy to 

 justify any \'ery extensive series of obser\'ations. Therefore the 

 number of measurements was restricted to that judged sufficient 

 to give merely an approximation of the apparent average and 

 range obser\'e{l. 



Till-; 'rii\ i;()ii) (;i.axi) 



The normal structure of the thyroid gland in the albino rat 

 at various ages will first be considered. Then the changes found 

 in the various types of inanition will be described and their sig- 

 nificance discussed. 



