1910.] The Chromaphil Tissues and the Adrenal Medulla. 507 



brown stain is fully developed, and the relations of the body can be 

 determined. 



It varies in length in the dogs I have dissected from 1 to 4'5 cm., and its 

 width varies from a very fine line to about 5 mm. 



c 



Text-fig. 3.— Ciromaphil Bodies of an Text-fig. 4. — Chromapliil Bodies of a 

 Adult Dog. Lettering as in previous Young Dog. Lettering as in previous 



figures. figures. 



Some illustrations of the variations in size and shape which may be met 

 with are furnished by the text-figs. 1 to 4. The body is flattened dorso- 

 ventrally, so that its thickness is not more than 0'2 to 0"3 mm. It varies 

 considerably in width from place to place, is frequently branched, and shows 

 broken-off portio'ns. The principal body is unpaired. 



Numerous irregularly placed small nodules of chromaphil tissue are seen in 

 different regions in more or less close connection with the principal chroma- 

 phil body (see text-figures 1 to 4, c). 



In the cat, the chromaphil bodies are not so large and dense as in the dog. 

 They have been fully described by Kohn*, and, as will be seen from his 

 drawings, as well as from those here given (text-figures 5 to 9), consist of 

 long threads of tissue instead of ribbons of varying width as in the dog. 

 These threads are stretched out along the sympathetic nerves, and the relation 

 of the chromaphil tissue to the sympathetic is closer, or at any rate more 

 obvious, than in either the dog or the rabbit. Small scattered chromaphil 

 corpuscles are found in different regions, as in the dog (text-figures 5, 6, 

 7. 8, c). 



In the vahhit, the threads of chromaphil tissue are thicker than in the cat. 



* 'Arch. f. niikr. Anat.,' 1903, Bd. 62, s. 31" ff. 



