166 BULLETIN UNITED STATES GEOLOGICAL SUEVEY. [Vol.YI, 



in liis diagnosis of the Felidce, and of the three comprehensive divisions 

 within which he places it : " I. Skull with the paroccipital process ap- 

 plied closely to the auditory bulla ; the mastoid process small or obso- 

 lete; externalauditorymeatus very short or imperfect. Div. A. Carotid 

 canal minute and superficial or obsolete ; condyloid foramen and foramen 

 lacerum posticum debouching into a common fossa 5 glenoid foramen 

 minute or null. Os penis rudimentary. Subdiv.l. Otic bulla divided by a 

 septum into posterior and anterior chambers, communicating by a narrow 

 aperture (Flower). Subdiv. a. SkuU with no alisphenoid canal." All 

 of the parts above mentioned I have found to be important in the defi- 

 nition of the natural divisions of the Carnivora, excepting those derived 

 from the paroccipital and mastoid processes. But their condition in the 

 extinct Carnivora which have been hitherto arranged with the Felidce,. 

 and which resemble them very much in superficial characters, does not 

 coincide with Professor Gill's definition. Thus, in the various American 

 genera which are allied to Drepanodon, the carotid canal is distinct from 

 the foramen lacerum posterius, and the condyloid foramen is also sepa- 

 rated from it by quite a space. These are characters which belong to 

 most of the Carnivora with five digits on all the feet. Further, the 

 postglenoid and postparietal foramina are present ; also characters of 

 the lowest Carnivora, as the bears and certain extinct dogs. Then,^ 

 there is an alisphenoid canal, which is also found in bears, dogs, and 

 the cat-like Cryptoprocta. I cannot demonstrate that the otic bulla is. 

 divided, as the above diagnosis requires, in any of the fossil species. I 

 have verified these characters on species of the following genera, of 

 which I have well-preserved skulls: Archcelurus, Wimravus, Binictis, 

 Pogonodon (except those of the basal axis of the skull), and Hoplophoneus. 

 Three genera as yet only found in Europe are similar in general char- 

 acters, and probably agree with them. I allude to Procelurus Filh., 

 ^lurogale Filh., and Eusmilus Gerv. On the other hand, the genus 

 Smilodon, which includes the American saber-tooths of Pliocene age, 

 agrees with the true cats in the points in question 5 i. e., the alisphenoid, 

 postglenoid, and postparietal foramina are wanting, the carotid foramen is 

 either internal or wanting, and the condylar enters the jugular foramen at 

 its mouth. This surprising condition of affairs makes it important to learn 

 the characters to be found in the species of the longest-known genus^ 

 Drepanodoji, of the European beds. But although there are several 

 good crania in European museums, T can find no description of their 

 nunute characters, and no mention made of their foramina. The proba- 

 bilities are, on various grounds, that this genus agrees with Smilodon in 

 the latter characters. The reasons in favor of this supposition are the 

 agreement in special dental characters, and the Pliocene age of the typi- 

 cal species, D. cultridens. Whether the middle Miocene species of San- 

 san and Epplesheim agree with this one in structure, is of course un- 

 certain. 



Seven, and perhaps eight, genera, then, constitute a group to be dis- 



