MEGA THERIID^E 



185 



of this family may be conveniently designated, agree with the 

 Sloths and Anteaters, and thereby differ from all other mammals, 

 in that the coracoid process of the scapula and the coracoidal 

 border of the same unite over the coraco- scapular notch, 

 which is thus converted into a foramen. Large clavicles are 

 present. 



Megatherium. 1 The typical genus Megatherium, as being the 

 longest known representative of the family, may be noticed in some 

 detail. A nearly complete skeleton, found on the banks of the 

 River Luxan, near Buenos Ayres, and sent in 1789 to the Royal 

 Museum at Madrid, long remained the principal if not the only 

 source of information with regard to the species to which it belonged, 

 and furnished the materials for many descriptions, notably that of 

 Cuvier, who determined its affinities with the Sloths. 2 In 1832 an 

 important collection of bones of the Megatherium was discovered 

 near the Rio Salado, and secured for the Museum of the College 



Fio. 61. Oral surface of mandible of Megatherium, americanum. 

 a, Condyle ; b, massetcric process ; c, angle ; d, symphysis. (After Owen.) 



of Surgeons of England ; and these, with another collection found 

 at Luxan in 1837, and now in the British Museum, supplied the 

 materials for the complete description of the skeleton published 

 by Sir R. Owen in 1861. Other skeletons have subsequently been 

 received by several of the Continental museums, as Milan and Paris, 

 and also by those in South America ; and consequently our know- 

 ledge of the organisation of the Megatherium, so far as it can be 

 deduced from the bones and teeth, is as complete as that of any 

 other animal, recent or extinct. 



The remains hitherto spoken of are all referred to one species, 

 Megatherium americanum of Blumenbach (M. cuvieri of Desmarest), 

 and are all from the newest or Pleistocene geological formations of 

 the Argentine Republic and Paraguay, or the lands forming the 



1 Cuvier, Tableau EUm. d'Sist. Nat. des Animaux, p. 146 (1798). 



2 An excellent figure of this skeleton, which unfortunately was incorrectly 

 articulated, and wanted the greater part of the tail, was published by Pander 

 and D'Alton in 1821, and has been frequently reproduced in subsequent 

 works. 



