1876.] PROF. FLOWER ON THE SKULL OF A X1PHODON. 5 



hind the large infraorbital foramen, is a wide and deep oval depres- 

 sion, extending over the whole of the region above the premolar 

 teeth. Indications only of such a depression are seen in the Tragu- 

 lidse. There is no vacuity at the point of junction between the 

 nasals, maxillae, lachrymals and frontals, as in so many Cervidae and 

 Antelopes, and as is slightly indicated in Ilyomoschus, though not 

 in Trayulus. The sutures bounding the lachrymal bone, and be- 

 tween the maxilla and malar, are beautifully marked by deeply in- 

 dented and wavy lines ; but the premaxillary suture cannot be dis- 

 tinguished, being probably situated anteriorly to the point of frac- 

 ture of the skull. The supraorbital foramina are not very large, 

 and are placed in depressions rather nearer the middle line than the 

 margin of the orbit, on a level with the anterior angle of that 

 cavity ; and, as in many existing Artiodactyles, a groove is continued 

 forwards from them. 



The posterior margin of the orbits, if, as is probable, they were 

 originally complete, have been broken away, as lias the entire zygo- 

 matic arch. 



Turning to the base of the skull, the occipital condyles are lost ; 

 but the greater part of the basioccipital, with its pair of pr minent 

 tubercles, remains. On each side of this the oval form of the liases 

 of the large auditory bullae can be distinctly made out, though they 

 have been worn level to the rest of the surface of the skull. Their 

 interior, however, can be seen to be rilled with a fine network of 

 cancellar tissue — a character common to the Suidae, Tragulidae, and 

 Camelidae, and absent in nearly all the true Ruminants. On the 

 lower surface of the skull, as well as above, the elongation of the 

 middle region is a conspicuous feature. 



The hinder margin of the palate is produced backwards to the 

 extent of fully three quarters of an inch beyond the notches on each 

 side ; but as its edge has been broken off, it is impossible to describe 

 its true form. 



Between the teeth the surface is long, narrow, and depressed 

 along the middle line. There is no sign, even at the anterior frac- 

 tured edge, of the incisive foramina, which must consequently have 

 been small ; but there is a conspicuous foramen opening forwards 

 near the outer edge of the palate opposite the second premolar tooth, 

 and placed rather more posteriorly on the left than on the right side. 



The alveoli, in most of which broken roots of teeth remain, form 

 a continuous series along each side of the palate, as far forward as 

 the line of fracture. Posteriorly they have been so much injured 

 that their form and number cannot be made out with perfect cer- 

 tainty ; but they appear to indicate teeth of the following character. 



Beginning at the hinder end of the series, there are three molars, 

 with four roots, wider transversely than from before backwards. 

 The most anterior of the three must have been considerably smaller 

 than the other two, which appear to have been nearly erpial in size. 

 In front of the molars there are seven roots, rounded or transversely 

 elongated, placed in a single line, and nearly .equidistant, indi- 

 cating a series of compressed teeth, each with an anterior and a 



