THE 



AMERICANJOURNALOFSCIENCE 



[FOURTH SERIES.] 



Art. XXII. — A Pleistocene Ground Sloth, Mylodon harlani, 

 from Rock Creek, Texas ; by Richard Swam Lull. 



[Contributions from the Marsh Publication Fund, Peabody Museum, 

 Yale University.] 



Introductory 



Locality 



Associated fauna 

 Geologic age 

 Specific summary 

 Morphology 



Axial skeleton 

 Skull 

 Mandible 

 Vertebrae 

 Pelvis 

 Ribs 

 Appendicular skeleton 

 Scapulas 

 Fore limb 

 Hind limb 

 Taxonomic summary 

 Bionomy 

 Relationships and distribution 



Introductory. 



Two years ago it was the writer's privilege to conduct an 

 expedition to the Panhandle of Texas with the avowed and 

 fulfilled purpose of obtaining for the Peabody Museum at Yale 

 a mountable skeleton of a fossil horse, Equus scotti, to add to 

 the classic series of equine remains assembled by Professor 

 Othniel C. Marsh. 



We went at once to the type locality near the head of Rock 

 Creek, and reopening the old quarry explored by Mr. James 

 W. Gridley in the interests of the American Museum of 

 Natural History, soon secured the needed skeleton. In the 

 meantime we were made aware of a hill farther up the canyon 



Am. Jour. Scl- 

 22 



•Fourth Series, Vol. XXXIX, No. 232.— April, 1915. 



