SUPRARENAL BODIES IN FISHES. 55 



h. HOLOCEPHALA. 



In CMmcfra monstrosa (PL IX. fig. 1) from the examination of four well-preserved 

 specimens, I find the suprarenals arranged almost exactly after the type of the 

 Plagiostomes. There is the same interrenal, unpaired as in the Dog-fishes ^, enlarged 

 and rounded posteriorly and broken up at its anterior end. There is also the same 

 arrangement of the segmental bodies, the only noticeable difference being that the 

 anterior pair, instead of being elongated and irregular, are smooth and regular oval in 

 shape (Pl.IX. fig. 1, ax.h.)^. They are, nevertheless, many times larger than any of 

 the other bodies of the same series. 



2. GANOIDEI. 

 Among Ganoids I have only been able to obtain representatives of two families of 

 the Chondrostei, viz., Acipenser sturio and Polyodon folium. The Polyodon was a 

 spirit-specimen in a bad state of preservation, and I could find nothing in the way of 

 suprarenals, so that I am limited to the Sturgeon for information about this order. 

 The Sturgeon is practically the only Ganoid it is possible to examine in anything like 

 a fresh state in this country. I have been able to obtain and have carefully examined 

 two specimens whose tissues were, to all intents and purposes, in a living condition. 

 The first specimen was 1-65 metre in length, with a kidney 63 centim. long; the 

 second was 2*14 metres, with a kidney of 1 metre. 



The suprarenals in the Sturgeon are " ochre-yellow " bodies of precisely the same 

 tint as the interrenal in Elasmobranchs. They vary extremely in size and shape, and 

 are scattered in a more or less irregular manner throughout the substance of the 

 kidney (PI. X. fig. 8, s.r.). They are for the most part finely lobulated, almost 

 coarsely granular to the naked eye, and many of the larger ones have processes or 

 claws extending out in various directions into the kidney-substance. A certain 

 number of the larger bodies are visible on the surface of the kidney, or revealed with 

 very little dissection. A still larger number come into view on slitting up the 

 posterior cardinal sinus, since they lie in abundance in its walls and in the immediate 

 neighbourhood. A large residue, including the majority of the smaller bodies, are 

 only revealed by digging away the kidney-substance in various parts. 



I find the larger bodies placed anteriorly (PI. X. fig. S) ; and in this respect my 

 observations differ from those of Leydig, who says that the larger ones are posterior. 

 It is quite possible that the arrangement differs in different specimens. I found none 

 whatever in the hinder fifth of the kidney, and by far the larger number, at least of 

 bodies of any size, were in both my specimens in the anterior seventh, /. e., just behind 

 the lymphatic head-kidney (PI. X. fig. 8, h.k.). Thus the most striking feature 

 about their arrangement is their extreme anterior position as compared with Teleosts. 



' leydig describes a paired " suprarenal," but although my specimens were old, yet I am convinced tlmt 

 there was a single median interrenal in each case. 



" [This appearance may possibly be due in part to the effect of long preservation.] 



