OEANIA OF EUMINANTS FEOM THE INDIAN TEETIAEIES. 3—90 
restricted by Hodgson and Gray. With the exception of the Buffalo all the wild 
cattle of India proper belong to the genus Bibos : I have not, however, in the 
Indian Tertiaries found the remains of any fossil species which belongs to this 
characteristic Indian group, though several of the fossil oxen approach this group in 
many points of structure of the cranium. 
Of the restricted genus Bos, I have described the crania of four fossil species, 
one of which is from the valley of the Nerbudda, and the other three are from the 
Sub-Himalayan Siwahks ; two species from the latter area, viz., Bos acutifrons and 
Bos planifrons, will be found to differ to a certain extent in the form of the occipital 
surface from the crania of any living species of oxen ; this divergence from the type 
form will be found carried to a stiU. greater extent in the occiput of Bos nama- 
dicus from the Nerbudda valley ; and the divergence is greatest of all in the living 
Indian wild cattle composing the genus Bibos. It is an interesting fact to note 
that the peculiarly formed occipital region of the living genus Bibos, at present 
exclusively confined to the oriental region, is found foreshadowed among the 
Indian fossil species alone of the many forms of the genus Bos ; in one species at 
least (B. namadicus) this abnormal form of the occiput is correlated with small 
premaxillse like those of Bibos, which are never found in any European ox. 
It may therefore not be improbable that Bos namadicus may have been one of 
the progenitors of the living wild Indian cattle. 
Bos planifrons, a new species from the Siwaliks, presents some points of 
resemblance to the Nerbudda species, but does not come very close to any living 
species. The long-horned Bos acutifrons is widely different from all other recent 
and fossil species, and presents certain affinities to Bubalm — the same remark will 
apply to the third Siwalik species, Bos platyrhinus. 
Bison sivalensis may probably be considered as the direct ancestor of the living 
Himalayan Bison {Boephagus) grunniens. 
The living Bubalus arni of India is without doubt the direct lineal descendant 
of the Bubalus palcEindicm of the gravels of the Nerbudda, and of the top- 
most beds of the Siwaliks. With regard to the propriety of making distinct species 
out of these two closely allied forms, we may note that the living wild cattle of the 
English parks and the aurochs of Lithuania are generally regarded as the direct and 
but little altered descendants of the fossil Bos primigenim and Bison prisons, and 
yet are frequently considered as distinct species in the modern modified acceptation 
of the term. It appears to me to be the best course to give a distinct specific name 
to every distinguishable form ; since it is only by describing the small varieties 
which exist between allied forms of the same type of animals that we are enabled to 
obtain evidence of the descent of one so-called species from another. It may here- 
after be advisable to invent a title which shall comprehend in one group all those 
so-called species which can be proved to be the lineal descendants of one original 
form ; the term species may either be taken in this larger sense or as the name of 
distinguishable forms of one period only. 
