1896.] Geology and Paleontology. 307 



cranial portion of the skull is shorter relatively than in Daorytkt mm 



and with this decrease in length I observe a greater development of 

 the anterior part of the brain case, which encloses the frontal lobes of 

 the brain. In short the brain of Tapirulus as compared with the size 

 of the skull, must have been much larger than in Dacrytherium, and 

 this greater development effected especially the frontal region of the 



As the Suilline type of skull was well established in the Phosphorites 

 or Upper-Eocene of France (Cebochcerus), I shall compare the cranium 

 of Tapirulus with that of Cebochcerus. In the latter genus the brain 

 case is very much reduced with the extremely prominent zygomatic 

 arches ; sagittal and lambdoidal crests are very heavy and the occiput 

 is broader than high. The cranial portion of the skull in Cebochcerus 

 is much heavier and broader than the facial. All these cranial char- 

 acters in Cebochcerus differ decidedly from those of Tapirulus and I 

 enumerate them, so as to prove that Tapimlus has no direct affinity 

 with the Suillines. The skull of Tapirulus somewhat resembles that of 

 the primitive Selenodonts, (Ccenotherium), but it is more slender and 

 its general form more closely resembles that of the Anoplotheridce. 



It is, however, the peculiar structure of the teeth, which is the most 

 important consideration in studying Tapirulus. It is upon the char- 

 acters of the teeth that Tapirulus has been assigned its various positions 

 in the Ungulata. On a superficial examination of the upper true 

 molars of Tapirulus, they exhibit a certain resemblance to those of the 

 Tapir, but studied in detail I shall endeavor to prove that the molars 

 of Tajnru/us differ fundamentally in their plan from any of the 

 known Lophiodonts. In the first place the external lobes of the supe- 

 rior molars in Tapirulus are concave, and not convex as in the true 

 Tapirine molar. Again the transverse crests are straighter and their 

 relation to the external lobes differ from those of the Tapirs tooth. At 

 the junction of the transverse crests and the external lobes there is a 

 strong notch, and in one specimen I can detect a faint trace of the 

 intermediate tubercles. 



The superior molars of the Anophtheriidcz. as is well known, have 

 deeply concave external lobes, the protoconule is distinct from the proto- 

 cone, the latter element being in its primitive bunodont condition. In 

 Anoplotherium and Dacrytherium the hypocone is selenodont in struct- 

 ure. In other words the form of superior molar found in the Anoplo- 

 theridce is a slight modification of the buno-selenodont type, it differs 

 from the exact form of this type in having the hypocone crescentoid. 



