70 



by Leydig (14) and Balfour (4), and finally settled by means of the 

 physiological test (Oliver and Schäfer, 18) by myself in 1897 (25, 

 29, 30, also see Moore and Vincent, 16 and 17). 



The relationship of the carotid gland to the medulla of the 

 suprarenal capsule and to the masses of chromogenic cells in connection 

 with the abdominal sympathetic was definitely pointed out by Stil- 

 ling (22), The suggestion as to the phylogenetic origin of the carotid 

 and coccygeal glands and the chromogenic cells of the sympathetic 

 ganglia from the "paired suprarenals" of Selachians was offered inde- 

 pendently by me in the following form: — 



"If the medulla of the mammalian suprarenal capsule be derived 

 phylogenetically from the series of paired suprarenal bodies of Elasmo- 

 branch fishes, it is probable that only those bodies in the region of 

 the kidneys and reproductive organs have actually entered into the 

 formation of the gland in higher animals. What has become of the 

 rest? Are they unrepresented in Mammalia? It is interesting to 

 note that certain cells are described in connection with the abdominal 

 sympathetic ganglion which are not nerve-cells and closely resemble the 

 medullary suprarenal cells. Kohn states that these become stained 

 brown with potassium bichromate. 



With regard to the paired bodies anterior and posterior to these, 

 it is not impossible that they may be represented in Mammalia by 

 such glands as the "carotid" and the "coccygeal". I would rather 

 throw this out as a suggestion than hazard it as an opinion (31, 

 footnote to p. 31)." 



This view has recently received full confirmation in the work of 

 Kohn (II) upon the carotid gland, in which he shews more clearly 

 than had been done previously the intimate relation between the 

 carotid gland and the sympathetic, and the identity of the chromo- 

 genic cells there found with those in connection with different ganglia 

 of the sympathetic chain. 



But Kohn takes rather a different view from my own as to the 

 morphology of the suprarenal constituents, and the physiological 

 significance of these extraordinary groups of cells derived from the 

 sympathetic which go to form the carotid gland (or a part of it) and 

 the suprarenal medulla as well as other bodies along the sympathetic. 

 So far as I understand him, he prefers to restrict the term "suprarenal" 

 to what is universally called the "cortex of the suprarenal" while he 

 calls the medulla of the suprarenal (along with the other similar 

 structures) "paraganglia" (8, 9, 10, 11). 



