Mylodon harlani, from Rock Creek, Texas. 333 



circumference. The coronoid process rises almost from its 

 middle. 



"Both radial diaphyses. These are live and a half inches 

 long, and four and a half inches in circumference about the 

 middle. 



" One ilium, two ischia, and an os pubis. Both femoral 

 diaphyses accompanied by the head of one. Length of the 

 diaphyses eleven inches ; circumference about the middle ten 

 inches. 



" A tibial and fibular diaphysis. The former measures four 

 and three-quarter inches in length, and seven inches in 

 circumference about the middle ; and the latter is about the 

 same length, and two and three-quarter inches in circumference 

 at the middle." 



Professor Cope* has described two new species of Mylodon 

 from Louisiana, referring the other material in the lot to 

 M. harlani. Of this latter species, the collection contains the 

 following teeth : a complete series of superior molars, all 

 separate, the anterior internal lobe of the third broken oif ; the 

 second, fourth and fifth of the superior series of the opposite 

 side, all separate ; the first, third and fourth of the inferior 

 series, all separate ; separate first and third inferior molars. 



Mylodon sodalis Cope. 

 Cope's original description^ of this species is as follows : 

 " The occurrence of this genus of sloths in Oregon was pointed 

 out some years ago by Professor Leidy, as indicated by a 

 specimen preserved in the museum of the Smithsonian 

 Institution, but the means of determining its specific relations 

 to the other species of the genus were not at that time extant. 

 A number of phalanges, including those of the ungues, 

 contained in my collection, demonstrate that the species of 

 Oregon was quite different from those of the eastern portion 

 of North America. 



" The ungual phalange selected for description has its basal 

 sheath developed on one side only ; its place is taken on the 

 opposite side by a prominent rim, which is tuberculate and 

 notched. The rim is low on the superior part of the proximal 

 extremity, and is separated from the articular cotylus by a 

 concave subvertical surface, wider than long. The basal 

 tendinous insertion is subdiscoid and flat, with a lateral 

 projecting rim, which is pierced at the base by the arterial 

 foramina. The general form of the phalange is more com- 

 pressed than in Mylodon harlani. Its superior middle line is 



*Cope, E. D., Proc. Amer. Philos. Soc, vol. xxxiv, p. 458, 1896. 

 f Cope, E. D., Bull. U. S. Geol. and Geog. Surv. Territories, vol. iv, p. 

 385, 1878. 



