Dr. J. E. Gray on Pigs and their Skulls. 437 



applied to, but separate from, the side of the nose, without 

 any or only a very slight indication of a cross ridge ; not de- 

 veloped in the females, and its usual situation indicated by 

 a sharp-edged ridge just above the lower margin of the upper 

 jaw in front of the grinders. The males have a deep concavity 

 on each side of the roof of the hinder upper part of the 

 inner nostrils ; in the females this part is only slightly 

 concave. I cannot find any exit from these pits, which are 

 very deep. 



Blainville figures the skeleton of a female and gives a cross 

 section of its skull, and also the skull of a male. He re- 

 presents the canine tooth of the female as just appearing 

 out of a very short sheath on the side of the upper jaw, con- 

 siderably above the lower edge. It probably may be the 

 skeleton of a young male ; at least the skull in the museum, 

 said to be a female, does not show any indication of the 

 canine. 



The bullae of the ears are oblong and elongate. No such 

 concavity exists in the back of the nasal cavity in any of the 

 pigs that I have examined ; but there is a deep pit on each 

 side of the centre of the hinder part of the nasal cavity in 

 PhacochopTus, which is small in the young and larger in the 

 more adult skulls. In the adult skulls there is a very deep 

 concavity on each side of the roof of the inner nostiils in front 

 of these pits, wdiich are separated from each other by a thin, 

 erect, longitudinal plate. These concavities are scarcely per- 

 ceptible in the skulls of the very young animals. 



The bullae of the ears of the skulls of the very young Pha- 

 cochcerus are large, nearly hemispherical, and very prominent ; 

 but in the adult skulls they are small and scarcely separated 

 from the rest of the skull. 



Babirussa. 

 Canines of the males elongate, convex at the sides, the 

 lower ones rounded, scarcely keeled in front ; of the females, 

 wanting in the upper jaw, and only short, conical, and slightly 

 recurved in the lower. 



Babirussa alfurus. 

 The skulls of the adult males present two very distinct 

 varieties. In one the upper and lower canines are very long 

 and gradually arched; in the other the upper and lower 

 canines are short, not more than three inches long, the 

 upper ones being very much curved, sometimes nearly into a 

 circle. 



