348 



DR. R. BROOM ON SOME NEW 



and the left mandible has been completely detached and lost 

 before f'ossilisation. 



The skull as preserved measures 198 mm. and was probably 

 about 202 mm. in greatest length. The greatest width across 

 the squamosals has been about 90 m)n. From the fiont of 

 the snout to the front of the orbit is 90 mm. The greatest 

 width of the snout in the canine region is 45 mm., and the 

 narrowest measurement between the supraorbital edges is 39 mm. 



The premaxilla is relatively small, and is much overlapped by 

 the maxilla. It sends upwards between the nostrils a slender 

 internasal process to meet the nasal above. Most of the teeth 

 are lost, but portions of three are stil seen, and from the sockets 

 the number and size of all can be determined. Tliere is evidence 

 of six incisors, of which the 6th is very small. The whole six 

 measure 24 mm. At the front end of the premaxilla are two 

 moderately Large foramina for branches of sensory nerve — 

 presumably a branch of tlie second division of the Yth. 



The sepfcomaxilla lies along the outer border of the nostril, and 

 passes backwards a short distance between the nasal and maxilla. 

 Between the septomaxilla and maxilla there is, as in other 

 previously known early carnivorous Therapsids, a large foramen, 

 the significance of which is at present unknown. In most fcetal 

 mammals there is a large gland duct developed along the outer 

 side of tlie nasal cavity, which from its very early development is 

 evidently the remains of some structure once of much greater 

 importance. It seems not improbable that this laige foramen, 

 which passes into the nasal cavity between the septomaxilla and 

 maxilla and is continued as a wide groove for some distrince 

 upwards and backwards tdong the upper border of the maxilla, 

 was for the lodgment of the glandular and possibly sensory organ 

 whose rudiment is met with in vAost mammals. 



The nasal is long and narrow, but broader at each end than in 

 the middle. The shape and relations will be best understood 

 from the figures given„ 



The maxilla is a powerfully developed bone of considerable 

 depth. There is a single large canine which unfortunately is not 

 well preserved on eitlier side. In front of the elevation which 

 accommodates the root of the canine, the maxilla overlaps the 

 premaxilla as in most Therocephalians, and in the anterior part 

 of the bone ai-e three fairly large foramina,, presumably for 

 branches of the Vth nerve. In the canine region tlie surface of 

 the bone is considerably pitted, probably by glands in the skin, 

 and there are a number of small openings, apparently for nerves. 

 The maxillaiy branch of the Vth nerve apparently passes into 

 the maxilla by a large foramen on the inner side of the bone 

 behind the canine, and passing forwards outside the canine, comes 

 to the surface through the numerous small foramina in the 

 front of the bone. Behind the canine there is a long slender 

 alveolar margin, which is remaikable in having no trace of molar 



