556 



3335. The skull of a male Babyroussa. 



The crown of the first true molar, ml, is much worn. The pterygoid sinuses are large 

 and complex. 



Presented by John Gaitskell, Esq. 



3336. The skull of a male Babyroussa. 



The base of the skull has been removed, showing the communication between the sphe- 

 noidal sinus and the pterygoid cells. 



Presented by Dr. Wallich t F.R.S. 



33'37. The skull of a male Babyroussa. 



The enamel has been abraded from the summit of the first molar, m 1, and the base of the 

 skull has been removed, but shows no communication between the pterygoid cells and the 

 sphenoidal sinus. 



Hunter ian. 



3338. The skull, with much of the dried integument, longitudinally bisected, of a 

 male Babyroussa. 



The sphenoidal sinus communicates with the left pterygoid sinus, both outer and inner 

 divisions of which are largely developed.. The petrosal, or bony capsule of the acoustic 

 organ, which does not coalesce with any of the elements of the temporal in the Babyroussa, 

 has been detached on one side. All the functionally developed incisors are here preserved, 

 the outer ones below having no homotype above. Both the first and second premolars are 

 suppressed in both jaws. There is no ossified prenasal. 



Presented by Joseph Vernon, Esq. 



3339. Skull of a female Babyroussa. 



The tusks are comparatively short in this sex. The tubercles of the penultimate, m 2, and 

 last, m 3, molars are very slightly abraded. The first and second premolars, p 1 & p 2, are 

 not developed. The suppression of the first and second upper premolars in most individuals 

 of the Sus Babyroussa appears to be due to the inordinate length of the upper canines and 

 the up-bent direction of their long sockets, characteristic of the species. Their homotypes 

 are equally undeveloped in the lower jaw, in which the canines are also very long. The 

 external incisors are absent in the upper jaw, but rudiments of their sockets may be discerned. 

 They are normally developed in the lower jaw. 



Presented by Dr. Babington. 



3340. The skull of a female Babyroussa. Hunterian. 



3341. The skull of a female Babyroussa, with small and simple pterygoid fossae. 



This specimen is from Sumatra. 



Presented by Daniel Moore, Esq. 



