330 PHILOSOPHICAL TRANSACTIONS. [aNNO 1787. 



fish often attempt to swallow what is larger than their stomaclis can at one time 

 contain, and part remains in the oesophagus till the rest is digested. 



The epiploon on the whole is a thin membrane; on the right side it is rather 

 a thin net-work, though on the left it is a complete membrane, and near to the 

 stomach of the same side becomes of a considerable thickness, especially between 

 the first 2 bags of the stomach. It has little or no fat, except what slightly 

 covers the vessels in particular parts. It is attached forwards, all along to the 

 lower part of the different bags constituting the stomach, and on the right to 

 the root of the mesentery, between the stomach and transverse arch of the 

 colon, first behind to the transverse arch of the colon and root of the mesen- 

 tery, then to the posterior surface of the left or first bag of the stomach, behind 

 the anterior attachment. In some of this tribe there is the usual passage behind 

 the vessels going to the liver, common to all quadrupeds I am acquainted with ; 

 but in others, as the small bottle-nose, there is no such passage, which by the 

 cavity behind the stomach in the epiploon of this animal becomes a circumscribed 

 cavity. 



The spleen is involved in the epiploon, and is very small for the size of the 

 animal. There are in some, as the porpoise, 1 or 2 small ones, about the size 

 of a nutmeg, often smaller, placed in the epiploon behind the other. These 

 are sometimes met with likewise in the human body. 



The kidneys in the whole of this tribe of animals are conglomerated, being 

 made up of smaller parts, which are only connected by cellular membrane, 

 blood-vessels, and ducts, or infundibula; but not partially connected by con- 

 tinuity of substance, as in the human body, the ox, &c. : every portion is of a 

 conical figure, whose apex is placed towards the centre of the kidney, the base 

 making the external surface; and each is composed of a cortical and tubular 

 substance, the tubular terminating in the apex, which apex makes the mamilla. 

 Each mamilla has an infundibulum, which is long, and at its beginning wide, 

 embracing the base of the mamilla, and becoming smaller. These infundibula 

 unite at last, and form the ureter. The whole kidney is an oblong flat body, 

 broader and thicker at the upper end than the lower, and has the appearance of 

 being made up of different parts placed close together, almost like the pavement 

 of a street. The ureter comes out at the lower end, and passes along to the 

 bladder, which it enters very near the urethra. The bladder is oblong, and 

 small for the size of the animal. In the female the urethra passes along to the 

 external fulcus or vulva, and opens just under the clitoris, much as in the human 

 subject. 



Whether being inhabitants of the water makes such a construction of kidney 

 necessary I cannot say; yet one must suppose it to have some connection with 



