1870. ] ANATOMY OF THE PRONGBUCK. 353 
ducts or crypts, which are found on the floor of the urethral cavity, 
at its anterior half, in the membranous groove between the inferior 
portions of the compressor muscle (ew). The glandular tubes open 
by separate puncta within the urethra. Where these terminate at 
the bulb and narrowing of the urethral passage, there is a semilunar 
free fold of membrane, forming a short cul-de-sac 0:2 inch deep. 
The bulbo-cavernosus (B. c), the ischio-cavernosus (I. ¢), and the 
retractores penis muscles (2. p, R. p*) are each fairly developed. 
The preputium (p) is attached by a freenum 0:9 inch from the 
tip of the penis. The glans is relatively thick posteriorly, but flat- 
tened in front; the tip being of an expanded spatular figure, with 
the corpus spongiosum and meatus urinarius (m. u) barely projecting 
beyond the terminal border, and not forming a long, free, whip-like 
process, as in some ruminants. 
The testes are small, each being under 14 inch long. 
9. OsTEOLOGY. 
Condition of the Bones.—I have strong reasons for suspecting 
that the unhealthy condition of the body affected the bones; but if 
not, these are remarkable for their lightness and porosity throughout 
the whole skeleton; indeed, as Mr. Gerrard, Sen., remarked, no 
ruminant skeleton of equal size possesses such delicacy of osseous 
texture. Comparing the other crania of the Prongbuck in the 
British Museum with our specimen, they did not feel nearly so light, 
but nevertheless sufficiently attested such absence of solidity that 
some might infer it as a quality predominant in the bony frame of 
this creature. 
If one were to speculate upon this fact, it might be given as one 
reason for the extraordinary fleetness of the creature. Their rapi- 
dity of speed is related as something marvellous. ‘Travellers agree 
that they outstrip a swift horse. Audubon’s account* is unique ; men- ~ 
tioning the several gaits, he concludes, ‘‘ While so rapidly do their 
legs perform their graceful movements in propelling their bodies 
over the ground, that, like the spokes of a fast-turning wheel, we can 
hardly see them, but instead observe a gauzy or film-like appearance 
where they should be visible. 
A. The Cranium. 
(a) Skull as a whole.—In profile (fig. 6, B) the cranium is remark- 
ably elongate antero-posteriorly, and shallow vertically. The summit 
and base run almost in parallel lines, so as to give great flattening or 
shallowness from above downwards. This is very unlike most of 
the living Cervidee and Bovide, where the frontal region is lofty and 
slopes downwards and forwards often sharply. Some of the Bovines 
(Bubalus, for example) have a tendency to upper levelling of the skull ; 
and among Antelopes such genera as Oreas and Alcelaphus exhibit 
lowness in the cranial vault ; but in all of these the resemblance is 
* Op. cit. p. 198. 
