SECTION OF THE MASTODON HEAD. 121 



see the whole extent of the nasal passage. The anterior external edge of 

 this passage is transversely oblong, and is about six inches in length. The 

 extent from above downwards is three inches. This aperture opens into 

 an enlarged sinuosity, in which are seen orifices leading to neighboring cells. 

 The nasal tube contracts to about two inches in diameter; then expands 

 into a broad surface a little excavated, which turns down behind the os 

 palati, and opens, between this and the pterygoid process, into the pharynx. 

 "We see protruding into the passage, part of the crown of a molar tooth. 

 At the anterior part of the nasal cavity is seen a canal running the whole 

 length of the face, and terminating anteriorly and inferiorly in a fissure 

 between the premaxillary and palatine plate of the maxillary bone. This 

 canal is fifteen inches long, half an inch in diameter, begins in the nasal 

 fossa, and is about a line in diameter at its termination. 



The remainder of the section of the face is occupied by cells lining the 

 entrance to the nasal cavity, and below by other cells occupying the pala- 

 tine portion of the maxillary and palatine bones. 



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