Douglass: Procamelus from Upper Miocene of Montana. 165 



of a small dromedary. Many skulls of the living species are very 

 much larger than that of Procamelus madisonius. The characters 

 which now seem most striking in the skull and dentition of this species 

 are the following : 



The posterior portion of the skull is broad in proportion to the 

 length. The posterior border of the orbit is about one third the 

 distance from the occiput above the occipital condyles to the anterior 

 margin of the premaxillaries ; thus making the brain-case and the face 

 shorter in proportion to the total length of the skull than is the case 

 in Procamelus occidentalis as figured by Cope on Plate LXXVII of 

 Vol. IV of the " U. S. Geological Survey of the looth Meridian." 

 The brain-case is still larger in Procamelus elrodi. The first and 

 second incisors in the type of P. madisonius are gone, but none of the 

 other teeth are greatly reduced. In P^ the inner crescent is incom- 

 plete. The length of the molar series is a little greater than that of 

 the premolar series. The three diastemata between I ^ and P^ increase 

 in length backward. 



