CEANIA OE EUMINANTS EEOM THE INDIAN TEETIAEIES. 71—158 
this part of the cavity is triangular in shape with a slightly vaulted roof, with well- 
marked ‘Hmpressiones digitatce the orbital cavity is smooth and rounded, and 
pierced by the supra-orbital foramen. The dimensions are as follows : — 
Inches. 
Interval between base of horn-core and orbit ...... 0’9 
„ „ bases of born-cores ........ 2 0 
Thickness of frontal .......... I'O 
Antero-posterior diameter of left horn-core ....... 1'8 
Transverse „ „ . . . . . . . 1’6 
The presence of the large supra-orbital fossa and foramen, the latter passing 
directly from the surface of the frontal into the orbit, at once separate the specimen 
from the sheep and goats, in which the foramen is small and has a sinuous course, 
and there is no fossa present : the horn-cores also taper much less than in any 
goat or sheep of the same size. 
The concavity of the frontals between the horn-cores and the raised frontal 
suture is an Antilopine character ; the horn-cores are placed on the frontals at a 
considerable distance apart, but not more so than in Saiga tartarica ; from their 
nearly uniform diameter they were probably of considerable length ; their ultimate 
direction cannot be determined from this specimen ; if continued outwards in the 
same manner as the part remaining, they must have differed considerably from those 
of any existing species of antelope ; possibly they were suddenly bent inwards after 
a certain distance, as in Alcelaplius. 
Antilope poppecticobnis, n. sp. nohis. Plate 25, f. 4. 
A large number of frontal bones and horn-cores of a species of antelope 
different from any of the above have been collected by Mr. Theobald from the 
Siwaliks of the Potwar district ; no complete crania have hitherto been discovered ; 
for this species I propose the name of A . porrecticornis. 
The specimen figured is the frontal bone, and the greater portion of the horn- 
core of the left side ; the right side has been restored in outline. The frontal is 
strongly arched, and excavated longitudinally between the prominent suture and 
the base of the horn-core. The supra-orbital foramen is enclosed by a large pyri- 
form sulcus, its extremity reaching almost up to the base of the horn-core. The 
horn-core is placed immediately above the orbit, and is separated by only a short 
interval ; the diameter of the horn-core is at first upwards, outwards, and backwards, 
and then curves inwards towards its extremity ; the transverse section is oval, the 
horn-core being compressed laterally. The measurements of the specimen are as 
follows : — 
Length of frontal suture 
Inches. 
2-40 
Width of frontal „ , . 
1-85 
Length of fragment of horn-core 
4-60 
Antero-posterior diameter of base of horn-core 
160 
Transverse „ „ „ 
116 
