The Comparative Histology of the Suprarenal Capsules. 289 



further and further backwards, there is less and less nervous admixture, 

 till the most posterior bodies present the type of suprarenal tissue, 

 with the ganglia quite separate from them. A fibrous capsule sends 

 in irregular septa, and capillary plexuses follow these. The arteriole 

 above mentioned always occupies the centre of the section, and 

 surrounding this is the "medulla" containing the chromogenic cells. 

 These have already been described in connection with the first pair. 

 PI. XVI. fig. 1 and PI. XVIII. fig. 3 represent these cells from the middle 

 region of the body of Raja clavata. External to these is a layer 

 several rows deep of irregular polygonal cells which shew no brown 

 coloration in bichromate preparations, and immediately beneath the 

 capsule is a layer of very irregular, elongated, almost columnar cells, 

 likewise shewing no pigmentation (PI. XVI. fig. 2). The nuclei of all 

 these cells shew distinct nuclear figures. 



Chevrel [18] differs from Balfour [3] in failing to find any 

 distinction between the character of the cells in the external and 

 internal zones of the paired bodies. This Author indeed goes so 

 far as to state that no definite cell-outlines can be made out in 

 any portion of the bodies. "On ne voit ni cellules columnaires à la 

 périphérie, ni cellules polygonales au centre; il n'y a que des apparences. 

 Et ces apparences sont dues vraisemblablement au contours des mailles 

 de la trame conjontive des corps. Les dissociations nous donnent 

 également des résultats négatifs." 



In my former descriptions I was inclined to agree on the whole 

 with Chevrel, but I have since then, as the result of continued 

 investigation, seen reason to alter my views. Even before tlie paper 

 was printed I had stated in a footnote "Since the above was written 

 I have* succeeded in making out the cell outlines in the 'axillary 

 hearts' and by renewed preparations by different methods I have 

 now no difficulty in determining the outlines of the cells in nearly 

 all the bodies. Moreover, "definite cells in some parts" were 

 described . . . "mostly triangular or multipolar in shape, and of a 

 uniform sepia-brown tint, and they contain large, very darkly stained, 

 round nuclei . . . The cells appear in some places to communicate 



Internationale Monatsschrift für Anat. u. Phys. XIV. 19 



