220 TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY, 



the pylorus, the lower surface of the stomach and the 

 distended gall bladder. The bile duct (Bd.) lies imme- 

 diately underneath it. It is covered over or attached by 

 the mesenteric sheet connecting the duodenum and suc- 

 ceeding portion of the intestine to the liver. A prominent 

 branch of the coeliaco-mesenteric artery (A.sji. fig. 22) 

 supplies it with blood. It is oval in shape, and in a large 

 fish is about 1 to 2cm. in longest diameter. It is black in 

 colour, and is very soft and easily torn. Its structure is 

 the characteristic splenic one. There is a strong fibrous 

 investment which is continuous with strong trabecule 

 passing inwards and dividing the whole gland up into 

 lobules. The reticular formation within the lobules is 

 filled with the characteristic splenic pulp, and in the 

 centre of each lobule is a mass of densely aggregated 

 lymphoid cells round which the texture of the pulp is 

 looser. A prominent vessel passes to each of these 

 nodules. This structure is best seen in the organ of quite 

 small fish, as in larger specimens it is much more obscure, 

 and granular masses of black pigment are abundantly 

 present. These pigment masses are composed of rounded 

 granules of variable diameter. 



The Supra-renal Bodies are situated on the morpho- 

 logical dorsal (spinal) surface of the kidney on the perpen- 

 dicular surface which is apposed to the 1st haemal spine 

 at about J of the length of this surface from the extreme 

 tip of the kidney. To display them the kidney must be 

 removed from the body, and since this is difficult on 

 account of the soft pulpy nature of the organ in the fresh 

 condition, the dissection is most conveniently carried out 

 on preserved specimens. The structures in question are 

 then seen as two oval or rounded bodies lying close 

 together, one on each side of the middle line to right and 

 left of the common genital artery (A. gen.) at the point 



