Megalonyx Laqueatus. 75 



laqueatus, lately described by me, as portions of this part of the 

 skeleton of this species, were found at the same time and place. 

 The individual, of which the remains now described, were a part, 

 was older and larger than the one discovered at White Cave, Ken. 



" This clavicle* belonged to the left side, is long, flattened, and 

 slender, curved somewhat like the human clavicle. The sternal 

 extremity is thickened and hemispherical, where it forms the ar- 

 ticulating surface : the scapular extremity is compressed, and fur- 

 nished on the inner, or inferior surface, with strong tubercles for 

 the attachment of ligaments. The anterior, or superior aspect 

 of the sternal extremity, is marked by an arterial groove. The 

 length of the clavicle is seventeen inches, the greatest circum- 

 ference, four inches ; the breadth one inch and eight-tenths ; the 

 greatest thickness, one inch. 



" The fragmentf I am now about to describe, is a portion of 

 the dexter lower jaw of the Megalonyx, containing four molar 

 teeth ; three of the crowns of these teeth are perfect, that of the 

 anterior one is imperfect. These teeth differ considerably from 

 each other in shape, and increase in size from the front, the 

 fourth and posterior tooth being double the size of the first, and 

 more compressed laterally : it is also vertically concave on its 

 external aspect, and vertically convex on its internal aspect; 

 the interior, or mesial surface is strongly fluted, and it has a 

 deep longitudinal furrow on the dermal aspect, in which respect 

 it differs from the tooth of the M. Laqueatus, previously described 

 by me,J of which the dermal aspect is uniform, but to which, in 

 all other respects, it has a close resemblance. I suppose it there- 

 fore, probable, that this last may have belonged to the upper 

 jaw. The three anterior molars, differ in shape, and markings: 

 they are vertically grooved, or fluted, on their interior and pos- 

 terior aspects, a transverse section presenting an irregular cube. 

 The length of the crown of the posterior molar is two inches ; 

 the breadth about five-tenths of an inch : the length of the tooth 

 is three inches and six-tenths. The diameter of the penultimate 

 molar is eight-tenths by seven-tenths of an inch. The length of 

 this fragment of the jaw bone is eight inches and four-tenths ; the 

 height three inches and six-tenths : the length of the space oc- 



♦ Figure 7, plate 3. t Plate 3, %. 1, is a flat view of the Jaw, looking 



down. Fig. 2, the interior aspect. Fig. 3, the exterior aspect. 



X No. 4, is the fluted surface ; No. 6, the external, or dermal surface ; and No. 

 6, the crown of that tooth. 



