548 Dr. C. I. Forsyth Major — PUohyrax from Samos. 



Orycteropus and the Ostricli are also associated, in the contemporary 

 beds of Samos) might be accounted for in a satisfactory manner, if 

 Leptodon could be shown to be related to the Hyraces. Against 

 such a relationship is opposed the large heel of the Leptodon's last 

 molar; so that an affinity with Titanotherium, as suggested by 

 Schlosser and Von Zittel, seemed to be more probable. 



The skull in the Geological Department of the British Museum 

 (No. M 5,419), briefly noticed by me in last month's Geological 

 Magazine (p. 507), was received from a dealer, labelled Bhinoceros 

 pachygnathus, Wagn., and determined by me as Leptodon, for the 

 reasons stated in my notice. 



The skull is represented on PI. XXIV, Fig. 1, of half natural size, 

 left side view. The right side is damaged, and the anterior extremity, 

 as seen from the figure, is wanting. The outline of the posterior 

 part is misleading, as it seems to represent the contour of the 

 occiput ; this is due to the objectionable practice of shaping the 

 matrix where the bone is absent, so as to make the specimen appear 

 more perfect ; the fossil was received in this state. What appears 

 as the postero-inferior angle of the skull is the post-glenoid process. 

 On the upper side of the skull the posterior part of the frontals and 

 the upper parts of the parietals are missing, but the matrix beneath 

 is preserved almost intact, so as to compensate partly for the missing 

 bone. Temporal crests are thus seen to have been present, and 

 these, starting from the posterior margin of the orbits, and con- 

 verging backward, unite to form a sagittal crest, at a point situated 

 approximately above the anterior border of the glenoid articulation. 



The orbits are comparatively small, closed behind, situated high 

 up and far backward (above m. 3). 



The zygomata are very high throughout, short and strongly 

 arched ; their shortness backward from the orbit is of course in 

 relation with the latter's posterior position. 



The infraorbital foramina are situated far backward, their 

 posterior margin corresponding to the anterior part of m. 1. The 

 bony palate is prolonged posteriorly beyond the molar series, so that 

 the anterior border of the choance is situated about 25 mm. behind 

 a line uniting the posterior ends of the two m. 3. 



The true molars, which are considerably worn, present the 

 following characteristic features : — 



First of all the great elongation of m. 3, due to an additional third 

 lobe, a sort of posterior heel. A common feature of the three true 

 molars is the strong development of the outer cusps, numbered 1 and 

 2. The molars also appear to be less lophodont than we shall find 

 to be the case in recent Hyracidse ; although much worn, they show 

 traces of two cusps on the inner side. The conformation of the 

 external parts of m. 1 and m. 2, showing only two protuberances or 

 cusps, separated by a fold, is at first somewhat puzzling, and 

 necessitates my entering into some further particulars. The outer 

 part of upper molars of Ungulata being represented by a greater 

 number of cusps, the question is, which cusps are missing in these 

 much worn molars. 



