THE SYSTEMATIC ANATOMY OF A FCETAL SEA-LEOPARD. 235 



raised areas, circular in contour, representing the bases of the renal pyramids : these 

 are mostly uniform in size, but some, smaller than the majority, lie rather below the 

 general surface. A mesial coronal section of the kidney passes through many of 

 the pyramids and also opens up the calyces and pelvis ; according to Chievitz,* a 

 certain amount of reduction takes place during development, so that whereas in certain 

 instances about two hundred calyces may be present, in the full-grown animal only 

 one hundred and forty remain, the reduction apparently commencing in those of the 

 6th and 7th order of origin. 



The ureter emerges from about the middle of the inner and dorsal margin of the 

 kidney, and passes down parallel to the mid-line, crossing the Miillerian ducts dorsally at 

 right angles, and finally opens dorsally into the lower segment of the bladder ; the 

 hilus of the kidney from which the ureter emerges and into which the renal vessels 

 pass is not a marked feature. The "pelvis" mentioned above is also but little 

 developed, since the ureter divides almost at once into two main branches, the latter 

 undergoing further subdivision in the kidney until the final divisions are reached 

 close to the surface of the organ in the cortical zone of each renal pyramid. 

 Each kidney measures about one inch by half an inch. The adrenal bodies (PI. XXI. 

 fig. 4) are small reniform structures lying one on each side just anterior to the 

 kidney ; there is a loose connection with the latter organ by means of a peritoneal 

 band. In actual shape the adrenal is a flattened pyramid with a convex base facing 

 outwards and ventralwards, whilst the hilus is placed at about the middle of the 

 inner, or rather dorsal, edge, close to the vertebral column ; the length of each gland 

 is half an inch, and the breadth one quarter inch. Some points in the histology of 

 both the kidney and the adrenal gland will be described later. 



(vi.) The genital glands with their ducts (PI. XXI. fig. 4) are in the present 

 specimen already sufficiently established to be able to determine the sex of the animal 

 — i.e. they are ovaries, and the Fallopian tubes pass from the outer ends of the glands 

 to fuse in the middle line dorsal to the bladder and ventral to the rectum, and from 

 the rudimentary uterus ; the outer ends of the Fallopian tubes are dilated to form 

 large ampullae for the reception of the ova, and these ampullae lie ventral to the 

 outer pole of each ovary. 



Each gland is an ovoid body lying obliquely from without backwards and inwards 

 just behind the posterior pole of the kidney ; from its anterior extremity an elongated 

 narrow muscular band, the diaphragmatic ligament of the mesonephros, passes 

 towards the diaphragm and becomes attached to the dorsal wall of the abdomen. 



The urinary bladder (PI. XXI. fig. 4 3 ) is an elongated organ attached above by a 

 patent allantoic duct to the umbilicus ; on transverse section, three apertures are seen 

 — a median one, the bladder, and two lateral, the lumina of the umbilical arteries. 

 The latter are passing to the umbilicus from their origin in the aorta. 



The bladder opens into the cloaca by a transversely elongated slit-like aperture, 



* Archiv Anat. u. Embryol., Supplement, 1897. 



