PROF. OWEN ON THE ANATOMY OF THE INDIAN RHINOCEROS. 35 
by a muscular and tendinous coat: the diameter of the excretory orifice (Ib. fig. 3) 
is about eight lines when fully expanded. 
The anus is dilatable to a great extent, corresponding to the large masses in which 
the faeces are discharged ; and the Rhinoceros presents, in the size of this aperture, the 
opposite extreme to the Giraffe and the Nilghau. 
A deep groove formed by two thick and prominent parallel folds extends from below 
the anus along the median line of the perineum, gradually widening, to the back part 
of the base of the preputial or pendulous part of the penis. In the ordinary retracted 
state of this organ, the distance from the anus to the preputial orifice is two feet ten 
inches: the length of the thick, wrinkled, tegumentary prepuce (PI. IX. fig. 4), within 
which the long glans is commonly retracted and concealed, is about nine inches ; 
its basal circumference measures one foot six inches ; on each side of this part there is 
a hemispheroid warty prominence (Ib. a). When the animal stales, the glans is pro- 
truded downwards with a curve backwards (Jb. fig. 5), and the urine is ejected between 
the hind-legs in a succession of jerks. I never saw it issue in a continuous stream. 
Under sexual excitement the penis is much further protruded and drawn forwards 
in a straight line (Jb. fig. 6). The singular form of the glans will be subsequently 
described. 
In the female Indian Rhinoceros, the vagina and the preputium clitoridis open on the 
external surface by two separate, narrow, vertically elongated orifices, each being, in the 
individual of nine feet long—the subject of the remarks on this sex in the present 
Memoir, about two inches in length: the vulva (Jb. fig. 7, vu) is immediately above 
the clitoris (Ib. fig. 8, c), i.e. nearer the anus. The extent of the perinzeum between the 
anus and vulva was four and a half inches. 
The nipples (Ib. fig. 8, m, m) were two in number and inguinal ; they were situated 
fourteen inches in advance of the vulva, and two and a half inches apart from one 
another. They were subcompressed, obtusely rounded at the extremity, and about two 
inches in length: about a dozen lactiferous ducts opened upon the somewhat flattened 
summit of each nipple. 
The integument on the middle line of the abdomen, along which it was divided in the 
operation of skinning, presented a general thickness of three-fourths of an inch. where 
it was cut on the inner side of the extremities, it was about one-fourth of an inch in 
thickness. It was connected to the abdominal parietes by a loose cellular tissue, and 
by a closer subcutaneous tissue to most of the other parts of the body; but the parts to 
which the stiff and ponderous hide most firmly adhered were the spinous processes of 
the posterior lumbar and sacral vertebra, and the anterior extremities of the iliac bones, 
at which places the corium was blended with the periosteum, and was remarkably thin. 
The hide adhered over the jugal bones to a kind of moveable fibro-cartilage ; and its 
attachment along the median line of the fore part of the head was so firm as to require, 
especially beneath the horn, the use of a chisel in order to separate it from the skull. 
