172 MR. OWEN ON THE OSTEOLOGY OF ORANG UTANS. 
and the application of the laniaries to be occasional, and probably defensive in most 
cases. The utility of formidable canine teeth to the Orangs, whose stature makes them 
conspicuous and of easy detection to a carnivorous enemy, is obvious ; such weapons, 
in connexion with the general muscular strength of the Pongos, may enable them to 
offer a successful defence against a large feline antagonist ; but in the smaller species, 
which we have been describing, to which concealment would be easier, the canines are of 
relatively smaller size, and those of the lower jaw are so placed as to be worn down by 
the lateral incisors of the upper jaw ; they were reduced in the specimen described, to the 
level of the other teeth ; and the points of the upper canines were also much worn. The 
size, forms, and proportions of the teeth which relate more immediately to the food of 
the Orangs, viz., the molars and incisors, show indisputably that the Simia Morio de- 
rives its sustenance from the same kind of food as the larger Orangs. The singular 
thickness or antero-posterior diameter of the incisors, which are worn down to a flattened 
surface, like molar teeth, show that they are put to rough work ; and it is probable that 
their common use is to tear and scrape away the tough fibrous outer covering of the 
cocoa-nut, and, perhaps, to gnaw through the denser shell. 
PLATE XXX. 
Fig. 1. Side view of the cranium of an immature Simia Wurmbii, showing part of 
the permanent series of teeth in place. 
2. Front view of the jaws of the same. 
3. Grinding surface of the teeth of the lower jaw, (the mark x denotes the 
lateral deciduous incisor not yet thrust out.) 
PLATE XXXII. 
Side view of the cranium of the adult Simia Wurmbii ; with a front view of 
the incisors and canines. 
PLATE XXXII. 
Base view of the cranium of the adult Simia Wurmbii. 
PLATE XXXIII. 
Side view of the cranium of Simia Morio, with a front view of the incisors 
and canines. 
PLATE XXXIV. 
Base view of the cranium of Simia Morio. 
a i i 
