4 MEGA-LONYX. 



confirmed the opinion of Dr. Wistar, that they belonged to an animal of the sloth 

 kind, in which determination he acknowledges the assistance of two additional 

 specimens, said to have been obtained by M. de Beauvois, from the same cave in 

 which were found those of Jefferson's collection. One of the new specimens, Cuvier 

 observes, " qui est une dent etoit surtout important, parce qu'il achevoit de faire 

 connoitre la nature de 1' animal." 



In relation to the locality from which the tooth just indicated was obtained, my 

 friend, Major Le Conte, has informed me that it was not found in the same cave in 

 which were discovered the specimens sent to Jefferson, but that M. de Beauvois 

 obtained it from Mr. Clifford, who discovered it in White Cave, Tennessee. 



Major Le Conte has further informed me that, at the time of the discovery of the 

 bones of Megalonyx described by Mr. Jefferson, numerous others were found. These 

 were carried away by different persons, and seem to have been all lost, except 

 several phalanges sent to President Monroe, and which are now preserved in the 

 museum of the Lyceum of Natural History, of New York. 



Dr. Harlan^ described some bones, which were found in Big-bone cave, Tennessee, 

 and referred them to a distinct species of Megalonyx from that indicated by the 

 specimens of Jefferson's collection, and gave to it the name of M. laqueatus, 

 while the other he called M. Jeffersonii. 



The specimens upon which the M. laqueatus was proposed. Dr. Harlan states, 

 consisted " of two claws, one rib, and several remnants ; os calcis, tibia, a portion 

 of the femur ; four dorsal and one lumbar vertebrse ; a portion of a molar tooth, 

 together with several epiphyses."^ All these I have satisfactorily determined to 

 belong to the Megalonyx Jeffersonii, as was j)reviously suspected by Mr. William 

 Cooper.® 



Dr. Harlan subsequently described the fragment of a lower jaw, and a clavicle, 

 which were likewise attributed to the Megalonyx laqueatus,*" but the former specimen 

 was determined by Prof. Owen, of London, to belong to a distinct genus, for which 

 the name Mylodon had been previously proposed on some remains discovered in 

 South America.^ 



Dr. Harlan further gave an account of an os ilium, from Big-bone cave. White 

 County, Tennessee, which, like all the newly discovered specimens, was attributed 

 to the M. laqueatus!^ 



Dr. Jeffries Wyman has described a tooth and the diaphysial portion of an un- 

 gual phalanx, from the vicinity of Memphis Tennessee,^ which, as will be hereafter 

 seen, are both attributable to the Megalonyx Jefferso^iii. 



Materials for Study. — The materials to which I have had access in entering upon 

 the description of the Megalonyx Jeffersonii are as follows : — 



^ Journ. Acad. Nat. Sci., VI, 269 ; Med. and Phys. Researches, 319. 



= Ibid., 2n ; Med. and Phys. Researches, 321. 



=> An. Lye. Nat. Hist., Ill, 166. 



* Monthly Journ. of Geology, t4; Med, and Phys. Res., 334. 



' Zool. of the Voyage'of the Beagle, pt. 1, 63. 



" Trans. Geol. Soc. of Penn., I, pt. 2, 347 ; Med. and Phys. Res., 336. 



' Am. Journ. Sci. and Arts, 2d ser., X, 58. 



