SUPEAEENAL BODIES IN FISHES. 73 



surrounding tissue of Lepidosiren. The specimen was a long-preserved one, and 1 

 could make out nothing with the naked eye. On cutting sections, however, the same 

 pigment-patches were obvious in the perirenal tissue as in Protopterus ; if anything, 

 these were more abundant in Lepidosire7i. Here, too, the resemblance to suprarenals 

 was greater than in Frotofterus, for I found not only small patches or individual 

 pigment-cells, but large rounded accumulations, which represent not continuous 

 columns, but spherical masses, thus approximating anatomically to adrenals. 



This tissue is of such great interest from many standpoints that I hope before long 

 to be able to give a fuller description of it in another place. I am persuaded that it is 

 really a " large-celled adenoid tissue," and some of the chief varieties of leucocytes can 

 be recognized in some of my sections. But the appearance in places is so very glan- 

 dular that Prof. Schafer, who has been kind enough to look at some of my slides, said 

 he should be very much inclined to think it might be suprarenal tissue, if a material 

 so very like it were not found in other places. In fact, the intestinal walls show 

 abundance of the same structure, and the spleen is very little different ^ 



I have carefully compared both these with the pigment-patches in other parts, and 

 find that they are quite comparable to these, so that, on the whole, I am inclined to 

 the view that they have nothing to do with the adrenals. 



Nevertheless, from a priori considerations, I believe that adrenals of some sort are 

 almost certainly present in the Dipnoi. These fishes closely approach the Amphibians 

 in many respects, and I am persuaded that could one obtain perfectly fresh specimens of 

 large size, suprarenals of a type resembling that of the Amphibians would be found -. 



My investigations upon the structure of the suprarenal capsules in Fishes all point to 

 their being hlood-vascular secreting -glands of two distinct kinds, and this coincides 

 entirely with the most recent views as to the function of the Mammalian organs. 



VI. The Relation of the Supraeenal Bodies to the Head-Kidney. 



1. Historical. 



Balfour (23 and 24) first clearly made out that in Acipenser and Lepidosfeus the 

 anterior dilatations of each kidney consist not of kidney-substance, but of lymphatic 

 tissue. He says, " Thus the tvhole of that part of the apparent kidney in front of the 



^ But, after all, it may be that there is no " great gulf " fixed between the leucocytes of adenoid tissue 

 and the cells of a secreting-gland. I hare recently seen a preparation from a case of Pagofs disease of the 

 nipple in the human subject which appeared to show a transition between the epithelial cells of the ducts and 

 ordinary leucocytes. See also Beard (Anat. Anz. ix. Band, Nr. 15, p. 481, and his references to Kolliker and 

 A. Prenant). 



- [Since the above has been in type, Petitt {he. cit. -pp. 67-GS) lias claimed to have found the suprarenals in 

 Protopterus. He says that in general form and relations they resemble those of the Teleostei, while iu minute 

 anatomy they are rather like those of Batrachians. But he gives no histological details, and says nothing 

 about cortex and medulla. — S. V., 10. 1. 97.] 



VOL. XIV. — PART III. No. 5. — April, 1897. L 



