EOTHEEIUM ^GTPTIACUM. 



211 



behind the canine alveolus are two more alveoli about the same size, and immediately 

 behind these again two small pits, the posterior of which is much the smaller ; at this 

 point the alveolar border of the jaw is thin and sharp. Separated from the last- 

 mentioned small pit by a very short interval are two rather small alveoli in close 

 contact. The anterior molar is separated from these alveoli by an interval of about 

 •7 cm. In the absence of teeth from the front of the jaw it is not possible to 

 determine the dental formula with certainty, but it seems that between the canine and 

 the molars there may have been two one-rooted premolars and two with two roots 

 each ; it is very probable, however, from Abel's account of the upper premolars, that 

 one (or perhaps both) of the pairs of alveoli assigned to the two-rooted premolars may 

 have been occupied by two (or four) single-rooted teeth. 



Text-fig. 67. 



Mandible of EotJierium cegyptiacum (?) : A, from above ; B, from left side. 

 c, canine ; i. 1-3, incisors ; m. 1-3, molars ; w./., mental foramina ; pm. 1-4, premolars ; sym., symphysis. 



About ^ nat. size. 



The molars may be described as bilophodont, each having a well-developed talon. 

 Each transverse crest consists of a low, blunt, outer cusp and a higher, sharper, inner 

 one. From the inner anterior angle of the antero-external cusp a ridge runs inwards 

 on to the front of the tooth ; from the inner anterior side of the postero-external cusp 

 a ridge runs across the main valley to the cusp in front. In the first and second 

 molars the talon seems to consist of a simple transverse ridge connected with the 

 inner end of the postero-external main cusp; in the third molar the talon is more 

 complex, and consists of three small elements, the middle one of which joins the 



2b2 



