CAIMANOIDEA VISHERI, A NEW CROCODILIAN 51 



(The lack of a rim gives the snout a distinctly mammalian appear- 

 ance.) " 



The teeth are well preserved for the most part and, with few 

 exceptions, have the crowns preserved entire. On the right pre- 

 maxilla, there are preserved four alveolae. On the portion of the 

 premaxilla broken away, there is apparently space for two addi- 

 tional alveolae, but there is possibly only one. In the latter case, 

 the total number is five, the number in the specimen described by 

 Loomis. Concerning this series but little can be said, as only the 

 circular roots of four remain. Of these the next to the last is the 

 largest, 5 . 5 mm. in diameter. In each maxilla there are appar- 

 ently thirteen teeth, a smaller number than is usually found in the 

 alligators. Of these the fourth is much the largest, fully 8 mm. in 

 diameter at the base and approximately circular in section. The 

 posterior maxillary teeth are all more or less laterally compressed. 

 The roots are oval in cross-section and in measurements range from 

 2 . 5 mm.X4 mm. to 4 mm.X 7 mm., the more posterior teeth being 

 the larger in general. The crowns of the first four maxillary teeth 

 are somewhat flattened on the inner side and present a slight 

 trenchant anterior and posterior edge. They are sharply conical 

 and very slightly incurved, perhaps. The crowns of the posterior 

 teeth show a rapid transition from this type to those with swollen 

 crowns, rather sharply conical in the first of the series and more 

 blunt or even of a rounded form posteriorly. A brief description 

 of the well-preserved eleventh maxillary tooth will serve well to 

 characterize this type. The crown is subglobular and is flattened 

 somewhat on the upper, inner surface. It is sharply set off from 

 the root by a marked necklike constriction. The apex is marked 

 by an indistinct, antero-posteriorly placed carina that does not 

 extend down on the sides. 



Of the posterior part of the skull but little remains except 

 the basi-occipital. The condyle is more or less spout-shaped and 

 is divided into two distinct surfaces by a well-marked median 

 groove. 



The palate is ahnost entirely lacking except for a small portion 

 along the maxilla-premaxilla union. At this point there is a deep, 

 sharply outlined pit for the reception of the fourth mandibular 



