SIWALIK AND NARBADA CARNIVORA. 
159—336 
Fig. 18. Machcerodus sivalensis (Falc. 
and Caut.). Outer view of left ramus 
of mandible of a male ; from the Siwaliks. 
Dublin Museum. 
haying' been chipped away. 
of the right ramus of a precisely similar mandible, obtained from the Siwaliks of 
the Riirki neighbourhood, and now in the Indian Museum. 1 It shows the three 
cheek-teeth, the summit of the main lobe of pm 4 being broken off : pm. 3 is very 
small, inserted by a single fang, and haying a sub-conical crown, with a minute hind 
talon. There is a rudiment of a talon to m. 1. 
Third specimen. — In figures 8, 8a of plate N. of the “ F.A.S.” there is represented 
a fragment of the left ramus of a mandible, with the three cheek-teeth ; correspond- 
ing in all respects with the last specimen. This jaw is in the Siwalik collection of 
the British Museum (No. 16,554). 
Fourth specimen. — In the accompanying woodcut (fig. 18) there is represented 
the nearly complete left ramus of the mandible 
of a Siwalik Machcerodus in the Dublin Museum. 2 
Posteriorly it is complete, with the exception of 
the coronoid process ; while anteriorly it is broken 
through the symphysis: it shows part ,of the 
alyeolus of the canine, and the greater portion of 
the descending expansion. The three cheek-teeth are 
preserved ; but in a more or less broken condition ; 
a large part of the outer surfaces of pm. 4 and ml 
These teeth agree with those of the preceding 
specimens, with the exception that pm 4, though still small, is inserted by two 
distinct fangs. The angular process and condyle agree in structure with those of 
Felis. The basal portion of the coronoid process (cr.) is extremely short antero- 
posteriorly, indicating the small size of that process, and that the skull had a 
prolonged zygomatic process, as in M. neogceus and M. necator. The descending 
sympliysial expansion commences some distance in advance of pm. 3, and descends 
very suddenly ; its posterior border being straight, and forming an angle of about 45° 
with the inferior border of the horizontal ramus. When complete this expansion must 
have been large ; indicating the existence of a long upper canine. The diastema 
appears to have been of medium length. 
Compared with the specimen represented in plate XLIV., fig. 4, it will be seen that 
the posterior border of the descending sympliysial expansion forms a smaller angle 
with the inferior border of the horizontal ramus ; and it seems probable that the 
whole sympliysial expansion in the former was not produced interiorly to such an 
extent as in the Dublin specimen : as, however, the two jaws agree in all other 
respects there can be little doubt of their belonging to the same species. Since the 
depth of the sympliysial expansion is generally correlated with the size of the 
canines, and as it is probable that these were larger in the males than in the females 
of the same species, it seems highly probable ■ that the Dublin mandible should be 
1 Obtained by exchange -with the Kurki Museum. 
2 One of the specimens purchased from Dr. Beattie (No. 49). 
