177—6 
SUPPLEMENT TO CRANIA OE RUMINANTS. 
cranium was thus named because of the remarkable resemblance of its horn-cores 
to the skull figured under the name of R. triquetriceros in fig. 2 of Plate H of the 
“ Eauna Antiqua Sivalensis,” in describing which the notes of Dr. Ealconer/ mention 
“ the remarkable triangular form of the horn-core,” and also because in describing 
the frontlet of Ampliibos acuticorms,^ it is stated that “the horns are rounded on 
their anterior surface and flattened behind.” On these grounds I thought that 
the specimen in question must belong to Remihos triquetriceros of Ealconer, and 
the specimen figured in Plate XXIV with horns rounded in front, to Ampliibos acuti- 
cornis. As, however, the latter specimen is now shown to belong to Remibos occi- 
pitalis [triquetriceros), in which the horn-cores are not generally triangular in 
section, the skuU drawn in Plate XXII must either belong to Ampliibos acuticornis 
of Ealconer or to a new species. None of the skulls figured under the latter 
name by Ealconer® have a distinctly triangular cross-section, but in a specimen 
figured by Professor Riitimeyer,^ the horn-cores are perfectly triangular in cross- 
section, and the skull (of which a side view is given) evidently belongs to the same 
species as my specimen (Plate XXII). Another skull recently acquired by the 
Indian Museum (Plate XXIIIA) has the anterior angle less distinctly marked 
than in my first specimen, and is in this respect intermediate between the latter 
and Ealconer’s large male skull the section of the horn-core in the new skull is, 
however, most markedly triangular. The horn-cores in the skulls figured by myself 
are also directed more upwards than are those of Ealconer’s type specimen, but 
these dilferences, with the help of intermediate forms, do not appear to be more 
than individual varieties, and I therefore come to the conclusion that the specimens 
referred to belong to Ampliibos acuticornis of Ealconer. 
Since we have found that both in Remibos occipitalis^ and in Ampliibos acuti- 
cornis of Falconer some forms have horn-cores with a triangular cross-section, 
and since the two are in other respects most closely allied, I now come to the con- 
clusion that they cannot be generically or sub-generically distinguished, and I there- 
fore propose to call the latter species Remibos acuticornis. 
The triangular-horned variety of Remibos acuticornis (Plates XXII, XXIII, 
XXIII A) is distinguished from the triangular-horned variety of R. occipitalis by 
its somewhat narrower forehead and less telescopic orbits, as w^ell as by the more 
upright direction of the horn-cores : it presents no close resemblance to the 
trochoceros form of the latter species. 
All the skulls of R. acuticornis hitherto referred to, are evidently those of 
males, the specimen figured in Plate XXII being evidently that of an old individual 
with the sutures obliterated. Another skull has, however, been figured by Rfiti- 
meyeU and Ealconer and Cautley,® which is referred by the former to the female ; 
’ Description of Plates of F. A. S. 
® F. A, S., Plate I. (lettered series). 
5 F. A. S., Plate I, fig. 2. 
f loc. cit., Plate III, figs. 4 & 5. 
^ F. A. S., Plate I, (lettered series), fig. 2. 
^ loc. cit., Plate III, fig. 7. 
« F. A. S., Plate H, fig. 2. 
8 F. A. S., Plate I, figs. 3 to 6, 
