135—48 CRANIA OF RUMINANTS FROM THE INDIAN TERTIARIES. 
magnum. In tlie cranium of tlie adult Arni this obliquity of the sphenoid to the 
plane of the palate is less than in young individuals, hut in no specimen that I have 
seen is there any approach to the identity of the planes of the two surfaces, seen in 
all the sjoecimens of the cranium of Bubalus palmindicus which have come under 
my observation. 
Again, if a transverse line he drawn across the frontals through the centres of 
the orbits of the two crania, the space between this and the intercornual ridge will 
form an almost exact square in Bubalus palceindicus ; while in Bubalus arni the 
antero-posterior diameter of a similar space will he one and a half inches longer than 
the transverse diameter ; this difference being partly due to the different forms of 
the anterior borders of the orbits described above. 
In Bubalus palceindicus the surface of the palate is produced backwards behind 
the last molar to nearly double the distance that it is in Bubalus arni ; in the former 
the length of the palate behind the last molar is 2’6 inches, and in the latter only 
1'3 inches ; the posterior nares are consequently placed much further hack in the 
fossil species. In both species the free edge of the palatines is mesially bisected 
by the vomer. 
The maxillo-palatine suture can just he distinguished in the figured specimen, 
and is placed entirely behind the posterior palatine foramina ; whereas in the recent 
species the suture bisects these foramina ; in both species the suture commences at 
the interval between the penultimate and ultimate molars, and at the median line is 
on a level with the interval between the antepenultimate and penultimate molars. 
The pterygoid processes of the alisphenoid are much larger and stouter in the 
fossil species, and extend lower down below the plane of the molar alveoli : the 
surface of the palate itself is also more arched from side to side. 
The horn-cores are placed on the frontals similarly in both species ; they are of 
larger size and directed more outwards in the fossil species ; specimens of the recent 
species from Assam and Cachar most nearly resemble the fossil form in this par- 
ticular. 
On comparing the occipital surfaces of the two crania, we find more differences 
than in the frontal aspects ; the occipital surface of Bubalus palcsindicus forms a 
very wide and flattened arch, with the crest distinctly and clearly marked, and its 
lateral borders convex ; this convexity causes the temporal fossae (perfect on the 
right side of the figure) to become very low and narrow ; on the occqDital surface 
the indentations of the fossae appear as pointed triangular slits on either side of the 
crest; the protuberance for the nuchal ligament is slight, and is not continued 
downwards as a sharp ridge to the foramen magnum ; this narrowness of the temporal 
fossae. Dr. Falconer says, is constant in all the specimens examined by him. The 
occipital crest of Bubalus arni forms a higher and more irregular arch, being 
flattened at the summit, and less prominently and sharply defined ; its lateral 
boundaries are somewhat concave, and the temporal fossae are consequently of con- 
siderable width throughout their length, and terminate superiorly in a blunt rounded 
