AND AFFINITIES OF POTAMOGALE. 13 



occupied by a ligament admitting of considerable motion between the two bones at 

 this spot. 



The femur is of the same length as the humerus, measured in each case from the 

 upper surface of the head to the distal extremity of the bone ; it has a prominent 

 tubercle, with a rough surface, upon the middle of the outer side of the shaft. 



The tibia is 1^ inch in length, measured from its upper to its lower articular 

 surface. The tibia and fibula are confluent with one another for the lower third of 

 their length. The tibia is curved, so as to present in its upper two-thirds an arch, 

 convex forwards. The fibula is a slender bone, forming the cord of the arch produced 

 by the curvature of the proximal two-thirds of the tibia. 



The tarsus is composed of seven bones. The calcaneum is large, and projects for 

 about one half its length behind the tibia. 



The metatarsal bone of the hallux is the shortest ; that of the outer toe is next in 

 length; and the metatarsal bones of the three middle toes are the longest, and are 

 nearly equal to one another. 



Anatomy of the Soft Parts. 



The imperfect state of preservation of the viscera, combined with the small amount 

 of time which it was pos.sible for me to spare from other avocations, has not allowed of 

 more than a fragmentary description of the anatomy of the soft parts of the animal. 



The stomach and the whole of the organs of digestion between this and the vent, 

 with the exception of about an inch of the terminal portion of the rectum, had been 

 removed before the specimen was placed in my hands ; so that certain important 

 characters, such as that derived from the presence or absence of a caecum, could not 

 be ascertained. The terminal portion of the canal, however, which escaped (fig. 9) 

 presents several points of interest. The rectum, instead of opening directly on the 

 surface of the body, opens into a sort of cloacal or postanal chamber, which also 

 receives the orifices of the vagina and urethra, and those of the ducts of a pair of 

 lai'ge anal glands. 



These glands are oval, about half an inch in their longer diameter. They are 

 situated immediately beneath the skin, one on each side of the postanal chamber, 

 into which each discharges its secretion by a single orifice. The excretory orifice of 

 each gland opens into the bottom of a little pouch formed by a fold of the lining 

 membrane of the postanal chamber at each side immediately within its margin. 

 Just behind the line where the cavity of the rectum becomes continuous with the post- 

 anal chamber, may be seen several very oblique pores in the mucous membrane of the 

 chamber — apparently the outlets of small submucous glands. 



The uterus and its appendages and the urinary bladder were also left behind in the 

 specimen ; but the kidneys had been cut away with the other viscera. The fundus of 



