80 ANTHROPOID APES. 



part of the temporal bones are connected by a wide 

 aperture with the sinuses of the greater wings and 

 pterygoid processes of the sphenoid bone. A sinus 

 which may be observed on the greater wing gene- 

 rally communicates by a large round hole with the 

 temporal cells. The^-e is generally, but not always, 

 a communication between the sinuses of the greater 

 wing and pterygoid process and the nasal cavity. 

 These cavities sometimes communicate with each 

 other through a wide aperture at the base of the 

 nose. The squamous part of the temporal bones 

 has a cellular sinus, which communicates with the 

 cells of the mastoid process, in its lower part with 

 the tympanum, and in its fore-part with the ossicles 

 of the lower wall of the tympanum. The maxillary 

 sinuses are in connection with the cells of the 

 lachrymal bone. There is nothing in the orang's 

 skull corresponding to the Vidian canal of the 

 sphenoid bone, but it may be traced in the gorilla 

 and the chimpanzee. 



The vertebral column of the orang has not the 

 same colossal spinous processes which distinguish 

 that of the gorilla. It differs also in many other, 

 though less striking, particulars both from the 

 gorilla and the chimpanzee. In the orang there 

 are generally twelve dorsal vertebrae, tapering in 

 their lower parts ; while their long, thick, transverse 

 processes, which are full of knots, take an upward 

 direction. The upper articular processes of the four 

 lumbar vertebrje present short and rather insig- 

 nificant mammillary processes. The sternum of the 

 young orang is generally formed of one large 



