No. 2391. DESCRIPTIONS OF PLEISTOCENE VERTEDRATA—HAY. 62.3 



ences in thickness. Measuring from the pillar on the outer face of 

 the anterior crescent to its inner wall the distance is 17 mm.; in 

 P. major it is only 14 mm. One must measure from nearly the bottom 

 of the fossette in order to get a width of 17 mm. The hinder crescent 

 of the Arizona specimen at the worn surface is 14 mm. wide; that of 

 P. major only 9 mm. It is only at the bottom of the fossette that 

 the width is 14 mm. These differences appear to be indication of 

 specific difference. 



Of a large camel there are some fragments of limb bones. One of 

 these is part of the distal end of a right tibia (Cat. No. 10156). 

 An estimate shows that the width of the lower end of this bone was 

 close to 93 mm. It lacks only 5 mm. of fitting into the right astrag- 

 alus of P. major. 1 * A complete bone is the right external malleolus 

 (Cat. No. 10157). Its greatest diameter is 52 mm., and it fits closley 

 against the right calcaneum. This calcaneum (Cat. No. 10158) 

 belonged to an animal that had not reached its greatest size, inasmuch 

 as the hinder epiphysis is missing. The length is now 146 mm. 

 The same bone of the dromedary has a total length of 141 mm. The 

 fossil calcaneum must have been originally about 165 mm. long. 

 The height at the external malleolus is 75 mm.; in the dromedary, 

 61 mm. A right navicular (Cat. No. 10159) has its greatest diameter 

 56 mm. ; in the dromedary this diameter is 48 mm. The fossil bone 

 fits quite exactly on the astragalus of P. major. 



There is in the collection a part of the shaft of a hinder cannon bone 

 (Cat. No. 10162), the length of the fragment being 185 mm. Proxi- 

 mally it reaches about the middle of the shaft; distally a little beyond 

 the top of the split. The fore-and-aft diameter of the upper end is 

 45 mm.; the side-to-side diameter, 40 mm. In the dromedary 

 these diameters are, respectively, 34 mm. and 30 mm. 



A fragment (Cat. No. 10175) which presents the distal articular 

 end of one of the divisions of a cannon bone is 50 mm. wide. In the 

 dromedary the width of the corresponding part of the anterior 

 cannon bone is 41 mm.; the width of this part of a metapodial of 

 Camelops huerfanensis , 40 mm. This bone has the size and general 

 appearance of the same part in the large camel which the writer 

 describes in this paper as Camelus maximus. When closely exam- 

 ined, however, differences are seen. The grooves alongside of the 

 guiding keels are deeper in C. maximus. While the side-to-side 

 widths of the articular surface is the same in the two bones, the fore- 

 and-aft thickness in C. maximus is 45 mm.; in the Arizona bone it is 

 50 mm. This bone may belong to a very large individual of Pro- 

 camelus coconinensis or it may represent an otherwise unknown form. 



A practically complete first phalange (Cat. No. 10163), probably 

 an anterior one, is present (pi. 122, fig. 6). The length in the median 



" Leidy and Lucas, pi. 18, fig. 1. 



