and its Position in the System. 325 



the inner surface, especially near the edge of the sheath. The 

 giraflfes, on the other hand, have the same permanent cores, which 

 are covered with a hairy skin, like the rest of the body, which 

 covers the horn during the entire life of the animal. 



The horns of the deer, with which Mr. Bartlett compares those 

 of the Prongbuck, on the other hand, are only developed at a 

 certain season of each year ; and while they are being expanded, 

 they are covered with a soft velvety skin containing a number of 

 large blood-vessels : these vessels become obliterated and the 

 skin falls off when the horns are fully developed; and at the 

 end of the season the horns themselves fall off, leaving only a 

 burr on the frontal bones. 



Now in the Prongbuck the core of the horn is permanent, 

 vascular, and exactly like the core of the horns of the true hol- 

 low-horned Ruminants, very unlike the deciduous horn of the 

 deer, and showing the true affinity of the genus to the antelope 

 and goat, with which it has been usually associated. It indeed 

 only differs from the normal structure of that of the animals of this 

 group in the core being covered with a case formed of aggluti- 

 nated hair, which falls off annually, and is replaced by another 

 case formed between its cavity and the outer surface of the core. 

 The surface of the core is covered with a vascular skin, which 

 secretes this deciduous coat of agglutinated hair, like the vascu- 

 lar coat that secretes and gradually enlarges and thickens the 

 horny permanent case of the horns of oxen, sheep, and goats. 



It is to be observed that the horny case of the core of all these 

 animals is formed of agglutinated hair; but the hairs of the 

 horns of the oxen, sheep, &c. are more closely agglutinated 

 and regularly placed, forming a denser substance than the 

 porous horny case of the Prongbuck, in which the several hairs 

 of which it is composed are to be seen by the naked eye, and 

 some of them projecting beyond its surface. 



I think that the above observation proves that the Prongbuck 

 is more nearly allied to the typical hollow-horned Ruminants, 

 with which it has been placed, than with the deciduous-horned 

 deer, with which Mr. Bartlett proposes to unite it. Indeed it 

 only differs from them in the outer case of the horn being po- 

 rous and formed of loosely agglutinated or, rather, felted hairs, 

 and in the case being deciduous and renewed annually, instead 

 of being permanent and strengthened by internal laminae so as 

 to form a hard horn. 



There is no doubt that this peculiarity of the structure and 

 derivation of the sheath, or rather case, of the horns affords a 

 very good character to separate the Prongbuck from the other 

 hollow-horned Ruminants; and I suggest that it should be formed 

 into a family, which should be called Antilocapridae, of equal 



