54 MEGATHERIUM. 



inner ones acute and rugged. The proximal end is narrowed, and is nearly five 

 inches in depth ; and the distal end is longitudinally oval, and presents a single, 

 vertical, articular convexity surrounded by a rugged border. 



The collection of remains of the Megatherium in the museum of the Academy of 

 Natural Sciences of Philadelphia, was presented to this institution by James 

 Hamilton Couper, of Darien, Georgia. These remains have additional interest 

 from the fact that they were obtained in a different locality from the others above 

 described or particularly indicated. They were discovered in association with 

 remains of Elephas primigenius, Mastodon, Bison latifrons^ Equus America^ius, 

 Chelonia Couperi, etc., in making the excavation of the Brunswick canal, which 

 connects the Altamaha and Turtle rivers, in Georgia.^ 



Mr. Couper'.s specimens are as follows : A portion of the hard palate ; a small 

 fragment of the alveolar border of the face ; the alveolar portion of the left side of 

 the lower jaw containing all the teeth; an anterior dorsal vertebra with its spinous 

 process lost ; two bodies of other anterior dorsal vertebrae ; bodies of two lumbar 

 vertebrae; two proximal extremities of ribs; the proximal extremity of a humerus; 

 and a lunar bone of the carpus. 



The portion of the hard palate corresponds to the anterior four molar alveoli, 

 and it belonged to a larger individual than the specimen above described, but other- 

 wise does not differ from it. When adapted in proper position with the small frag- 

 ment in the same collection, of the alveolar border of the face, the latter is estimated 

 to have been about six and three-quarter inches wide at the middle pair of alveoli. 



The fragment of a lower jaw containing the teeth also corresponds with the same 

 portion of the specimen belonging to the National Institute. 



The anterior dorsal vertebra has a trilateral body, the posterior face of which is 

 four inches wide and three and three-quarters in depth. The spinal canal is trans- 

 versely oval, and is three and a half inches wide and three deep. The spinal arch 

 at the root of the spinous process is five inches in width antero-posteriorly. The 

 transverse process is short, strong, and tuberous ; and it presents a concave articular 

 facet for the tubercle of the rib, and a second concave facet is situated at the side 

 of the spinal arch for the head of the rib. 



The two dorsi- vertebral bodies above mentioned correspond to that just described, 

 and all three of them are about three and a quarter inches in length. 



The two lumbar vertebral bodies are cylindroid, with dilated extremities, and are 

 about four and a quarter inches long, and five in diameter at their articular surfaces, 

 and their spinal canal is about two and a half inches wide. 



The two proximal extremities of ribs are from the posterior part of the thorax ; 

 and their heads measure three inches in the long diameter. 



The proximal extremity of the humerus in form resembles that of Megahnyx, 

 but its tuberosities are unequal in size. The breadth of the fragment at the 



' The fragment of a lower jaw upon which Dr. Harlan founded the Sus Americanus, and Professor 

 Owen, of London, the Harlanus Americanus, I find to belong to Bison latifrons. See Proc. Acad. 

 Nat. Sci., 1854, VII, 89. 



" The fossil bones were found at the bottom of an alluvial formation, between four and six feet below 

 the surface, imbedded in a stratum of clay resting ou yellow sand. Hodgson: Mem. on the Meg., 38. 



