r)G4 GEOLOGICAL SURVEY OF THE TERRITORIES. 



according to Marsli, but excavated on the margin only in Loxolophodon, 

 It is iieitber in Elephas. There is a postglenoid process niiicli more 

 largely developed than in Elcpliantidcv. Other differences of still less 

 importance are to be seen in the anterior position of the exterior nares, 

 and the presence of horns. 



The Baihmodontidw are represented by Bathmodon. With a structure 

 of the hinderlimb nearly reseml)]ing/!^o/v((,s//e»6', we have more i)ronounced 

 relationships to the Perissodactyles. The scapula has the massive 

 apical acumination of the IJlcjjhaniidw, and there is no round ligament 

 of the femur in some of them. The astragalus has the same flattened 

 form seen in Uintathcrimn, and is even less like that of the Perissodac- 

 tyla. The type of molars and the long compressed canines are similar to 

 those of Loxolopliodon. Ou the other hand, the cervical vertebra? are 

 rather longer, and there is a rudimental third trochanter of the femur. 



History^ tOc. I oiiginally referred the Eohasileidcn to the Prohoscidia, 

 ou account of the structure of the limbs, and subsequently stated a num- 

 ber of reasons for this conclusion at a meeting of the Academy of Natural 

 Sciences of Philadelphia, held January 14th, 1873, (i)ublished Jaiuiary 

 IDth.) In the i)resent ]):iper, numerous contirnjatory characters are 

 added. The BatJimodontidcv I have heretofore referred to the Perifiso- 

 dactyJa. 



ProfessorMarsh, in describing a species of this group, TUanotherium {f) 

 anceps, (July, 1871,) compares it with perissodactyle species, and in de- 

 scribing the tibia says that it, " at its proximal end, has the femoral sur- 

 faces contiguous, with no prominent elevation between them, resembling 

 in this respect some of the Prohoscidia.^^ A few days before the publi- 

 cation of my conclusions, in a foot-note, (July 22d, 1872,) he altered the 

 name Titanothcrium to 3[astodon, indicating that he had reached the 

 same oi)inion. Shortly aftei", (American Journal of Science and Arts, 

 September 27th,) he altered his view, constructing a supposed new 

 order "ii/jiocr ?•«?«," for their reception. 



As regards the name of the order here defined as including the four 

 families above mentioned, I have preferred using one already employed 

 to coining a new one. This is the better course also, if, as is not uidikely, 

 the distinctions ou which it, as well as the other two orders, "repose, shall 

 be broken down by new discoveries in paleontology. 



EOBASILEIDiE. 



The genera of this group known to the writer are four, which differ 

 as follows : 



1. Nasal bones with flat horizontal horn-cores overhanging their apex. 

 Cervical ^'etebne short; malar bone much reduced in 



front iMXolopliodon. 



2. Nasal bones with small tuberosities. 



(Cervical vertebne short Eohasileus. 



Cervical vertebrailouger; the malar bone reaching maxil- 

 lary face ' Uintailierium, 



3. Nasid bones without the anterior horn-cores. 



Cervicals {I) Megaceratops. 



The above is the closest approximation to nature which my present 

 material allows. It is not at all unlikely that the ditference in develop- 

 ment of the anterior nasal tuberosities seen in Loxolophodon cormitus 

 and Bohcmicus pressicornis will turn out to be onl}' specific. 



The dentition of this group requires special notice. ' Judging from the 



