REMAINS OF A BRITISH FOSSIL ZETTGLODON. 429 



and meet in the mesial line so as to form a flattened slightly convex 

 palate. On the superior surface these bones form a concave chan- 

 nel, which widens behind. The median suture [of the palate] is 

 overlain, for 4 inches, by a fragment of a thin bone J inch thick, 

 which appears to have been 1-J inch wide in the middle, and to have 

 narrowed in front and behind. Posteriorly it extends beyond the 

 maxillarics. This bone is presumably the vomer. External to it 

 laterally are the impressions of the premaxillaries, which were 

 about f inch wide where they rested on the maxillaries ; but behind 

 the third tooth the impressions of these bones widen rapidly and 

 converge towards the median line, as though they met posteriorly. 



The Teeth. 



The first two teeth in the maxillary bone were presumably simple 

 and conical crowns, with a single fang ; from the sockets for these the 

 teeth are gone. The first socket extends to within less than | inch 

 of the anterior termination of the jaw ; it is -J- inch long and | inch 

 broad, is ovate in section, and placed evenly between the inner and 

 outer sides of the jaw. Between this and the second socket is an 

 interspace of -f^ inch. This interspace is hollowed out on each max- 

 illary bone into a shallow hemispherical pit outwardly placed on the 

 alveolar margin, caused apparently by absorption due to the pressure 

 from a tooth in the lower jaw. The second socket is more than an inch 

 long, and less than -| inch wide ; so that it is more elongated than the 

 other. On the internal alveolar margin, behind these teeth, runs a 

 narrow elevated marginal ridge of bone. 



The next interspace is about T 9 ^- inch long ; towards the third 

 tooth it is excavated as though by pressure from a tooth in the 

 lower jaw. The third tooth is lf^ inch long, is compressed from 

 side to side, less than half an inch thick in the middle, and attenu- 

 ated to a sharp margin in such a way that the angle at which the 

 inner and outer sides of the tooth meet is less than a right angle. 

 The anterior and posterior parts of the crown are moderately serrated, 

 so as to form four small denticles on each side of the larger median den- 

 ticle which divides them. The denticles are much smaller in front than 

 behind. The cutting-margin of the denticles of the tooth is faintly 

 crenulated. Around the base of the crown runs a narrow elevated 

 cinguloid ridge of enamel, which does not extend mesialiy above the 

 fangs. The inner surface of the crown above these ridges is marked 

 with vertical striae on the enamel. The portion of the unenamelled 

 fangs which projects from the sockets is less than \ inch deep. The 

 height of the crown is less than an inch. The interspace between 

 the third tooth and the fourth is | inch. The fourth tooth is also 

 If inch long. Its crown, though equally high, has a different 

 aspect ; for the denticles are larger, longer, thicker, and more deeply 

 divided from each other than in the preceding tooth, so that the 

 outline of the crests of the denticles of each side is convex from back 

 to front. As in the third tooth, the posterior denticles are the 

 larger ; and the denticles are similarly crenulated. The cingular 



