Genito-iirinary A'pparahis of the Male Porpoise. 119 



probable that the small size of the bladder may be associated 

 with the quality of the urine, siuce the large size of the 

 kidneys points to a plentiful quantity of urine. Since, as 

 has already been stated, it appears very probable that all the 

 fluids taken by a Cetacean in, or with, its food-supply, are 

 of a highly saline character, one would also expect the urine 

 to be of a high specific gravity, and consequently, if the 

 urinary bladder had been of such a size as to permit of a 

 large accumulation of urine, it might have been difficult to 

 avoid the formation of sedimentary concretions in the bladder. 

 But there can be very little risk of such an occurrence when, 

 from the small capacity of the bladder, its contents can 

 never amount to more than a few ounces, and it must there- 

 fore be very frequently emptied. 



The Testes were situated upon the ventral wall of the 

 abdominal cavity posterior to the hinder ends of the kidneys, 

 but with the entire depth of the abdominal cavity between 

 the two sets of organs (PL II. Fig. 2). Each testis had thus 

 travelled through half of a circle from its original point of 

 development. Further, the hilum of each testis was turned 

 in the ventro-mesial direction, so that each had rotated 

 about its long axis through three-fourths of a circle. The 

 peritoneum associated with each testis provided a short 

 longitudinal mesorchium by means of which the testis was 

 attached to the ventral wall of the abdominal cavity. Each 

 measured 6"6 cm. in length, 3 cm. in breadth, and slightly 

 more than 2 cm. in thickness. They were thus almost 

 twice the size of the human testes. 



Each presented anterior and posterior rounded, and slightly 

 pointed, ends ; three surfaces and three thick rounded 

 borders. The borders were mesial, lateral, and ventral or 

 mesorchial. 



The dorsal surface, directed towards the abdominal viscera, 

 was flattened and slightly indented by pressure from intes- 

 tinal coils. 



The ventro-lateral surface was convex and smooth, being in 

 close apposition with the ventral wall of the abdomen. 



The ventro-mesial surface was also convex, and presented 

 numbers of indentations, the majority of which were due to 



