226—18 INDIAN TERTIARY AND POST-TERTIARY VERTEBRATA. 
Distribution . — All the known remains of this species have been obtained from 
the lower Siwaliks of Sind. 
Species 4. Ghaeialis leptodus (Falconer and Cautley^). 
Syn. Crocodilus fLeptorhynchusJ leptodus.^ Falconer and Cautley.^ 
History . — This species was never described by its founders, but two specimens 
are figured under this name in “Falconer’s Palseontological Memoirs,” vol. I. 
pi. XXIX. figs. 3 and 4. The latter may be taken as the type, as the former has 
been made the type of G. hysudricus. 
Mandibular rostrum . — The type specimen is represented from the oral and lateral 
aspects in plate XXXII. figs. 2, 2a, and comprises the hinder portion of the 
mandibular rostrum ; it was obtained from the typical Siwalik Hills, and is preserved 
in the British Museum. A very similar specimen, obtained by Mr. Theobald from 
the Siwaliks of the Punjab in 1875, is represented from the oral aspect and in section 
in figs. 3, 3a of the same plate ; it exhibits the greater part of the rostral portion of 
the splenials, and fifteen broken teeth on either side. These specimens differ from 
the rostrum of each of the three preceding specimens by their much greater relative 
width, and the proportionately smaller size of the teeth. Whereas in all the 
preceding species the length of the space occupied by three teeth is equal to at least 
two-thirds the width of the rostrum, in the present specimens the former dimension 
is not more than one-third the latter ; and the peculiarly flattened form of the 
mandibular rostrum is well exhibited in the section drawn in fig. 3a. The bevelling 
of the lateral borders is also much less strongly marked and the teeth (fig. 3b) have 
a more elliptical section, and are set with their longer transverse diameter more 
nearly at right angles to the long axis of the jaw. The entrance of the splenial 
element into the mandibular symphysis indicates the gharialoid nature of the species. 
In profile (fig. 2a) the mandible shows a considerable curvature, — the upper surface 
being concave and the lower convex. The pitting of the inferior surface is more 
marked than in 6r. gangeticus. Another specimen in the British Museum (No. 39807) 
apparently belongs to the mandibular part of the rostrum. 
Cranial rostrum. — The specimen represented in plate XXXII. fig. 4 was obtained 
from the Siwalik Hills, and is in the Indian Museum ; it comprehends a portion of 
the maxillary rostrum of a gharial agreeing so exactly in general proportion with the 
mandibles already described that there can be no doubt as to its belonging to the 
same species ; it comprises the region immediately in advance of the orbits, and 
shows ten alveoli on the left side. There is a strongly marked concavity in the 
preorbital region ; and but a slight bevelling of the lateral borders of the oral 
surface, the alveoli are of relatively small size, but this feature is not quite so strongly 
marked as in the mandible : the relative great width and flatness of the rostrum are 
very noticeable. This specimen is very important since it shows on the facial 
surface the termination of the nasals a short distance in advance of the orbits, thus 
1 “ Falconer’s Palseontologioal Memoirs,” vol. I. p. 355 (1868). — Crocodilus (LeptorhynchusJ. 2 Zoc. cit. 
