300 F. B. Loomis — Osteology and Affinities 



lated bones, and the four complete skeletons of the American 

 Museum. In the series are individuals which are interpreted 

 as male and female, and a number of young having but their 

 milk dentition. The species is named after Dr. Edward 

 Hitchcock, whose work in comparative anatomy and paleon- 

 tology was the stimulus for the expedition and the work of the 

 writer. The individual used for the type is one which 

 has just reached maturity as shown by having all the molars 

 worn, but that is all, for the epiphyses of several of the 

 limb bones are still free from their shafts. The position of the 

 type specimen is that of an animal which has just laid down 

 with legs outstretched and head thrown back, or probably 

 better, of an animal which has been drowned, but is natural 

 enough so that we can readily get measurements of the whole 

 animal. 



Height at the shoulders _.. 684 mm (27 in.) 



Length of head 1 75 mm (7 in.) 



Length of neck 380 mm (13J in.) 



Length of body 433 mm ( 1 7 in.) 



Length of tail 155 mm (6J in.) 



This individual is slightly smaller and lighter in build than 

 some of the others, and I have interpreted it as a female. In 

 comparing the measurements with those of other Tylopoda it 

 will be apparent that the body is unusually short ; the limbs, 

 therefore, appear long, though when compared with the 

 length of the humerus, they are but little longer relatively 

 than those of Poebrotherium. The neck in conjunction with 

 the increase of limb is also a little longer than that of the Oli- 

 gocene tylopod. 



Skull. — The relatively small skull lias a wide cranium but a 

 narrow compressed muzzle. The basicranial axis is only 

 slightly bent. In conformity to the lateral compression of the 

 muzzle the nasals are slender splints which diverge when they 

 reach the wedge-shaped anterior end of the frontals. These 

 latter bones are very wide, overhanging the orbits which stand 

 out from either side of the skull. The two parietals are fused 

 medianly and make a bone of considerable extent, on the pos- 

 terior half of which is situated a low sagittal crest, which unites 

 with the strong lambdoidal crest. This latter crest is high and 

 projects strongly backward, overhanging the occiput. The 

 premaxillse rise rapidly on the high muzzle, expanding some- 

 what at the upper end. It is the maxilla which makes up the 

 greater part of the side of the snout and in this bone are two 

 deep pits on either side, the first a preorbital pit, a little in 

 front of the orbit and high up on the muzzle ; the second a 

 subnasal pit, considerably in front of the former and much 

 lower on the muzzle. The preorbital pit, situated some 20 mm 



