570 DR. J. MURIE ON THE ANATOMY OF THE SEA-LION. 



preputial fold of skin continuous with the sheath is dark-coloured and much wrinkled, 

 both circularly and longitudinally, the latter cuticular furrows being remarkably small. 

 The prepuce is attached 1| inch behind the urethral orifice. The glans penis at its 

 thinner hinder end has dark-coloured mucous membrane ; but the bulbous terminal front 

 is more florid. The truncate extremity of the glans is oval, the long diameter vertical, 

 and the lower end the narrowest part. The somewhat prominent distal end of the bone 

 is covered by a layer of mucous membrane, between which and the outer glans there 

 is a shallow furrow. 



The os penis, a strong bone, is altogether 4 inches long, but in the present example of 

 Otaria angularly bent ; suffice it to say that in other examples of the genus the os penis 

 is more or less straight. The posterior extremity of the bone is thickest, the remainder 

 forwards to the glans penis roundish, and about 02 inch in diameter. At the distal end 

 it terminates abruptly in a vertically extended and laterally compressed truncation. 



Strange to relate, the animal during life had the misfortune to sustain a fracture 

 of the penis, though the exact nature of the injury was only revealed after death. 

 Either just before or immediately after the Otaria came into the possession of the 

 Society it was observed that the point of the penis protruded continuously through 

 the membranous sheath which usually encloses it. With this constant supposed partial 

 erection the glans and foreskin were inflamed and in a raw state. The tumidity &c. of 

 the parts suggested the probability of phymosis ; and it was proposed to alleviate the 

 malady by topical treatment, or operation if need were. Neither, however, was very 

 feasible ; and as the swelling gradually subsided, no further active measures were taken. 

 Time brought about a cessation of all bad symptoms ; but the glans penis was never after- 

 wards withdrawn within the sheath. At last it became leather-like and callous from 

 the continual rubbings it was subjected to as the animal walked and scrambled about 

 in its rough gravelly enclosure. On dissection of the body it was discovered that the 

 os penis was broken exactly in its middle. The bones had firmly united in the form of 

 an arch or obtuse angle ; that portion of the external limb of the arch within the glans 

 could necessarily never be withdrawn within the sheath. In the delineation of the 

 organs of generation (PI. LXXXII. fig. 73) this most remarkable piece of nature's surgery- 

 is shown, the asterisk pointing to the apex of the angle or seat of fracture. In the 

 figure in question the relative positions of the bladder, urethra, and penis are, of course, 

 altered from that which they had in the living animal ; notwithstanding, the amount of 

 bending in the bone is thoroughly appreciable. 



b. Muscles of the Genitals and Anus. — The retractors of the penis are two long, narrow, 

 riband-like muscles, which have origin among the fleshy fasciculi of the internal 

 sphincter and levator ani muscles anterior to the rectum. The retractors pursue a 

 parallel course along and under the surface of the penis, and are inserted into the 

 tissues connected with the prepuce. 



The membranous portion of the urethra has a thin layer of transversely striped mus- 



