5—213 
SIWALIK CEOCODILIA, LACERTILIA, AND OPHIDIA. 
Itecent Asiatic species. — The following species are found in Asia at the present 
day : — 
A. Palatal aspect of premaxillae short, with posterior border nearly straight. 
Crocodilus palustris,^ Lesson, India. Ceylon, and Burma. Facial portion of cranium (pi. 
XXIX. figs. 1. la.) very broad; sculpture deep; rugose nodules in advance of orbit; in- 
terorbital space narrow and deeply concave, its width being much less than long diameter 
of orbit ; premaxillary fissure heart-shaped ; maxillo-premaxillary suture usually extends on 
palate but slightly behind anterior border of fifth alveolus superior surface of premaxillse 
shorter than external narial aperture ; facial profile concave. In old individuals the facial 
part of the cranium is relatively wider, and more convex than in the young. 
Crocodilus siamensi.s, Schneider. Siam, and Cambodia. General characters of last species, 
sculpture on face much less deep, with slight nodules in advance of orbits ; interorbital space 
wider and flatter, its width being nearly equal to long diameter of orbit ; palatal aspect 
of premaxillse somewhat longer. 
B. Palatal aspect of premaxillae elongated, with centre of posterior border projecting into maxillae. 
Crocodilus porosus,^ Schneider. S. Asia, and N. Australia. Facial portion of cranium 
narrower than in C. palustris ; sculpture slight ; an elongated, longitudinal, sinuous ridge in 
advance of orbit ; interorbital space wide and somewhat concave ; premaxillary fissure a 
comparatively narrow slit ; maxillo-premaxillary suture extends on palate as far back as hinder 
border of sixth alveolus. 
Crocodilus pondicherianus. Gray. S. India. Founded on a young specimen ; general 
cranial characters apparently those of C. porosus. 
African species , — Africa is inhabited by the typical G. vulgaris., Cuvier, in which 
the facial portion of the cranium is oblong and narrow, with preorbital ridges, and 
with elongated premaxillse ; and on the western coast by O. catapJir actus, Cuvier, in 
which the face is much elongated, and the differentiation of the teeth but slight. 
Species 1. Ceocodilus sivalensis, n. sp. noUs. 
(Allied to G. palustris, Lesson). 
History . — The earliest notice of this form appears to be one by Clift,^ in which 
some specimens are recorded from the Siwaliks of Burma, which were regarded as 
indicating an animal closely alied to G. vulgaris ; a later memoir was published by 
Cautley,® in which three fragments of crania from the Siwalik Hills are described 
and figured. The cranium of a recent crocodile is figured for comparison, but was 
unfortunately misidentified ; it being named C. porosus [hiporcatus), whereas it really 
belongs to C. palustris. As the result of the comparison, the conclusion was arrived 
at that the fossil was a variety of the existing species, — i.e. of C. palustris, the main 
difference being that the premaxillse were relatively longer in the former. Manu- 
script notes by Falconer, preserved in the British Museum, appear to indicate that 
he took the same view of the affinities of the Siwalik form. 
Immature crania , — The British Museum possesses a large series of more or less 
1 Syn. C. bombifrous, Gray. 2 Occasionally it extends as far as the anterior border of the sixth alveolus. 
3 Syn. C. biporcatus, Cuvier. 4 ‘ Trans. Geol Soc.’ ser. 2. vol. II. pt. 3. p. 375 (1828). 
5 ‘Asiatic Eesearches,, vol. XIX. pp. 25-31. pi. II. (1836). Thetext is reprinted in ‘ Falconer’s Palfeontological Memoirs,’ 
vol. I. pp. 344-350, accompanied with figures of two crania. 
B 
