718 THE EOCENE FAUNA. 



Length of true molars .0138; fourth premolar short, .0045; anterior cusps of true molars 

 single P. brachystomus. 



Length of true molars .0105; fourth premolar small, .0035; without anterior cusps and 

 M-ith two ridges on heel ; true molars with double anterior inner cusps P. nuptus. 



I originally arranged this genus in the 3Ie$odonta, as only the dental 

 characters were then known. These resemble also those of the suillines, 

 where I once provisionally placed the genus Mioclcemis, which proved later 

 to be a creodont. The possession of the bones of P. brachystomus shows 

 that that species belongs to the Artioclactijla. 



A few bones, including metapodials, of the P. longicaudus, are preserved, 

 but it is from remains of the P. brachystomus that the characters of the 

 skeleton of this genus are derived. 



A lumbar vertebra of the M. brachystomus has flat articular surfaces. 

 The ilium has a rather long j^eduncle, much wider than deep, with a ti-ian- 

 gular section. The base of the triangle is rather short, and is concave. 

 The acetubular cotyloid notch is open. Femur with prominent greater and 

 lesser trochanters, but no third trochanter. Trochanteric fossa profound. 

 Head with fossa ligamenti teris isolated from neck. 



The characters of the tarsus are typically those of the order Artiodactyla. 

 The astragalus exhibits a distal trochlea which is continuous with the sus- 

 tentacular facet, and which articulates with both cuboid and navicular. 

 The distal portion of the fibula is free from the tibia, and its shaft becomes 

 very slender. It is possible that a more perfect specimen would display it 

 as continuous. Its distal extremity articulates with the ascending tuberosity 

 of the calcaneum. The cuboid facet of the latter is narrow. The cuboid 

 and navicular bones are distinct from each other and from the cuneiforms. 

 The mesocuneiform is shorter than the ectocuneiform, and is coossified tvith 

 it. There are probably four metatarsals. The median pair are distinct, but 

 appressed ; their section together, subcircular. The lateral metatarsals are 

 slender; the external one is wanting, but its facet on the cuboid bone is very 

 small. 



These characters are in general similar to those of the genus Dichobune, 

 but Cuvier does not state whether the cuneiforms are coossified in that 

 genus or not. They are united in Anoplotherium. Pantalestes difi"ers from 

 Bkhobune in the presence of but one internal tubercle of the superior 



