244 



TEETIAET VEETBBEATA OF THE EATtM. 



cutting-edges as in Zeuglodon, but the two posterior premolars and the first molar 



of the upper jaw have a postero-internal buttress, enamel-covered, and evidently the 



remnant of a postero-internal cusp : in the premolars at least this buttress is supported 



by a large distinct third root. 



Text-fig. 80. 



nar. 



Eestored figures of skull and mandible of Prozewjlodon atrox : A, from right side ; B, from above. 

 al., alisphenoid; ao.f., antorbital foramen; c, canine; cond., occipital condyles; fr., frontal; *. 1-3, 

 incisors ; ju., jugal ; la., lachrymal ; m. 1-3, molars ; mx., maxilla ; na., nasals ; nar., external nares ; 

 opt., optic foramen ; pa., parietal ; pgl., postglenoid process ; pm. 1-4, premolars ; pmx., premaxilla ; 

 p.orh., postorbital process of frontal ; soc, supraoccipital ; sq., squamosal ; zyg., zygomatic process of 

 squamosal. | nat. size. 



The genus is at present known only from one species, remains of which were found 

 in abundance by Mr. Beadnell * in a valley about 12 kilometres W.S.W. of Gar-el- 

 Gehannem, in beds of the Birket-el-Qurun series, a horizon beneath that in which 



* ' The Topography and Geology of the Eayum Province of Egypt' (Survey Department, Cairo, 1905), p. 47. 



