332 E. S. Lidl — Pleistocene Ground Sloth. 



from various localities which he refers to this species. The 

 list follows : 



1. Two fragments of the last molar in Mammoth Ravine, 

 Mississippi. 



2. Tooth and humerus, found on the Willamette, or Mul- 

 tonah River, a tributary of the Columbia in Oregon, referred 

 to M. harlani by Owen. 



3. A number of bones and teeth found by Mr. Koch, in 

 association with remains of mastodon, etc., in Benton County, 

 Missouri. These Harlan called Orycterotherium missouriense. 

 but Owen, who had an opportunity to see the specimens, 

 referred them to M. harlani. 



4. Humerus from Big Bone Lick, Kentucky, preserved in 

 the cabinet of the Academy of Natural Sciences, Philadelphia, 

 an adult agreeing pretty closely with M. rohustus, and its 

 measurements according with those of the Oregon specimen 

 described by Perkins. 



5. The collection of Dr. Dickeson, deposited in the Academy 

 of Natural Sciences, contains a number of bones of a half grown 

 M. harlani found in association with Megalonyx, in the 

 vicinity of Natchez, Mississippi. 



Leidy's description of M. harlani reads : 



" The left halt* of the lower jaw preserved with all its teeth. 

 The bone in its present condition measures ten inches from its 

 posterior margin to the anterior mental foramen, which is 

 placed an inch and a quarter in advance of the position of the 

 first molar ; and its depth below the third molar is about two 

 and a half inches. Its form agrees with the corresponding 

 portion of the jaw of Mylodon rohustus but is more convex 

 externally in accordance with its age. The teeth have the 

 same form and proportions as those in the adult fragment of 

 jaw above described, except that the first of the series in 

 transverse section is more demi-oval than reniform, and the 

 anterior side of the second tooth is a little convex instead of 

 being a little concave. 



" The malar bone of the left side. It presents the same 

 trilobate appearance as in Mylodon rohustus. 



" Fourteen fragments of vertebrae. 



" The scapula of the right side. Its glenoid articulation and 

 coracoid process have the same mode of development indicated 

 in the account of the corresponding bone of the young skeleton 

 of the Megalonyx jejfersonii. 



" Both numeral diaphyses. These are nine and a half inches 

 long, by seven and a half inches in circumference at the 

 middle. The deltoidal tract already presents a prominent 

 outline. 



" The right ulnar diaphysis, which is eight and a half inches 

 long, and its lower third is six and a quarter inches in 



