70 MR. SWALE VINCENT ON THE 



I have no doubt, from the above structure, that these bodies are representatives of 

 the suprarenale in Ganoids, and in my opinion they correspond to the cortical portion 

 in higher Vertebrates. 



3. TELEOSTEI. 



The minute structure of the suprarenal bodies does not exhibit any wide variation 

 throughout the different families of Teleosts. Between the individual members of the 

 families the differences are of course still less. There are, however, such differences, 

 and these appear to consist chiefly of variation in amount of fibrous tissue, variation 

 in blood-vascular supply, and in the shape of the alveolar compartments into which 

 they are all divided. 



The organs are surrounded by a capsule of very varying thickness (in the species I 

 examined from 4 to 70 /*), in close connection with which are sometimes found sympathetic 

 nerve-fibres and small ganglia, and blood-vessels. Outside the capsule there is usually 

 more or less adenoid tissue. In the majority of instances this is nothing more than 

 a local increase, in the neighbourhood of the suprarenals, of the ordinary renal inter- 

 tubular adenoid tissue. 



The capsule is always thicker throughout the area which is in contact with the 

 kidney. This is probably to be explained by the fact that we have a double layer, 

 consisting of the capsule of the suprarenal and the capsule of the kidney, fused 

 together at this paxt. There is never any direct anatomical connection between the 

 parenchyma of the suprarenals and kidneys, and, so far as I have been able to discern, 

 nothing to suggest that the suprarenals are parts of the kidney. 



The fibrous capsule sends iu trabecular, which divide and subdivide at first in a 

 rather irregular manner ; but ultimately they form in all cases very regular alveoli, 

 having about the same average dimensions as those of the interrenal of the Elasmo- 

 branchs (q. v.), strikingly suggestive of those of secreting-glancls, and these alveoli are, 

 as a rule, completely filled with the suprarenal cells, which are much smaller than 

 those of the interrenal of Elasmobranchs. But in some species (Conger conger, 

 Anguilla anguilla, and Salmo trutta) there is a more or less empty space in the centre 

 of each alveolus (PL XIV. figs. 45 & 46, c.sp.). These spaces are, however, never 

 complete ; one finds scattered cells, nuclei, and shreds of protoplasm, which suggest 

 that this space does not exist in life. Most probably the central cells of each alveolus 

 are more loosely connected together than the rest, or possibly they suffer a very rapid 

 post-mortem change \ In by far the majority of Teleosts a very regular row of nuclei 

 can be traced round the circumference of each alveolus, and in many cases their cell- 



1 [Pettit (Joe. cit.) has laid great stress on this peculiar structure of the alveoli in the Eel, looking upon it as 

 the fundamental type of a suprarenal gland. He finds a true physiological compensatory hypertrophy of one 

 gland after removal of the other, and urges that the body is a true secreting-gland. But he seems to be totally 

 unaware that the known suprarenals of the Eel and other Teleosts correspond to the cortex only of the 

 Mammalian gland, and that all we know about the function of the suprarenals so far is confined to the 

 medulla.— S. V., 10. 1. 97.] 



