THYMUS AND THYROID GLANDS. 849 



ever, that the iodine content of the thyroid is particularly as- 

 sociated with the presence of colloid matter. The large 

 accessory gland found in the median line high up in the 

 thoracic cavity, just above the upper end of the sternum, 

 weighed 36^ grams. From its location it was at first re- 

 garded as thymus. It showed a distinct "division into a 

 cortical and medullary portion, the latter constituting some- 

 what more than half the diameter of the entire body, and being 

 made up of fibrous tissue. The cortical portion resembles that 

 of developing thyroid tissue as described by Halsted* as 

 being found in dogs after partial extirpation of the thyroid 

 gland." In the central portion no iodine could be detected ; 

 in the cortical portion, within the spaces of which colloid mat- 

 ter was observed, no less than six milligrams of iodine were 

 found. It may be added that the patient had undergone no 

 previous treatment involving the use of iodine compounds, 

 which are well known to increase the iodine content of the 

 thyroid. 



The preceding details have been recorded not alone because 

 of the unusual conditions observed, but particularly because 

 they emphasize the care which becomes necessary in the re- 

 moval of thymus tissue, to avoid contamination with possible 

 accessory thyroids. In the parathyroids of the dog and rabbit 

 Gley f has found a relatively greater content of iodine than in 

 the thyroids of the same animals. 



The data to be presented in this paper include analyses of 

 both human and animal glands.J In searching for iodine, the 

 finely-divided, dried gland-substance was fused in a nickel 

 crucible with sodium hydrate and potassium nitrate, and this 

 process together with the succeeding colorimetric estimation 

 of the iodine in the fusion products was carried out accord- 

 ing to the directions of Oswald. Silver crucibles were never 



* Halsted, Johns Hopkins Hospital Reports, i. 



t Gley, Coraptes rendus, cxxv, p. 312. 



t Grateful acknowledgment is made to Professor H. B. Ferris of the Yale 

 Medical School and to Dr. Joseph Roby of Rochester, who have furnished 

 suitable material ; and particularly to Armour and Company of Chicago, who 

 have generously prepared various gland products for me. 



Oswald, Zeitschrift fur physiol. Chemie, 1897, xxiii, p. 275. 



