Dr. J. E. Gray on the Pronghorn Buck. 323 
H. Thetidis, and H. Derbianus, but is easily distinguished from 
them by the bright rusty red brown of the basal third of the 
ears, the space about their base, the spot over the eye, and the 
back of the hind legs, as well as by the greyish brown colour of 
the neck and fore limbs. The proportional measurements are 
also different. 
XLIII.—Notes on the Pronghorn Buck (Antilocapra), and its 
Position in the System. By Dr. Joun Epwarp Gray, 
F.R.S., V.P.Z.8., &e. 
In the ‘ Proceedings of the Zoological Society’ for 1855, when 
describing a pair of horns in the collection of the late Earl of 
Derby, I mentioned that the horn of the Prongbuck was “ formed 
of agglutinated hair, that it was lined internally with a close velvet- 
like coat of short hairs, which were directed towards the top of the 
cavity, and that the edge of the base of the horn was furnished 
with a rig of hair.” I observed that the “ peculiarity in the 
internal structure of thé horns of the genus showed, like the 
branched external form, a similarity to the horns of the deer, 
the hairy horns being the analogue of the deciduous velvet of 
the deer and the permanent hairy coat [on the horns] of the 
giraffe.” ; 
1. The peculiarity in the structure of the horn which isolates the 
Cabrit or Prongbuck from the other hollow-horned Ruminants 
seems to have been overlooked by the American naturalists; and 
the spoils of the animal are very rare in European museums. 
The hunters of America stated that the Prongbuck shed its 
horns; but the systematic zoologists, who depended on the ex- 
amination of the preserved skin and head for their facts, did 
not believe the assertion; and, indeed, some went so far as to 
deny the fact. 
When the hunters at Fort Union said that the prong-horned 
Antelope dropped its horns, Messrs. Audubon and Bachman 
(Quad. North America, p. 198) considered it a sufficient reply 
to show them that “the bony part of the horn and the hard 
spongy membrane beneath were well attached to the skull and 
perfectly immoveable.” They evidently had the deciduous 
horn of the deer in their mind, and could not conceive any 
other manner of shedding the horns, not foreseeing that the 
horny sheath might drop off the cores, which, if they had ex- 
amined the structure of the horn and observed its internal fur, 
they might have anticipated as probable. 
Cassin, in the ‘ United States Exploring ‘Expedition’ (p. 63), 
under Antilocapra americana, remarks, ‘‘ Dr. Pickering, in _ his 
