GIANT SLOTHS AND ARMADILLOS. 179 



Mr. Clift's memoir above quoted. But even then the materials 

 were not complete for a thorough knowledge of the bony frame- 

 work of the Megatherium, and it was not till 1845, when more 

 remains (discovered near Luxan, 1837) reached this country, that 

 Professor Owen was able to clear up one or two doubtful details. 

 These were purchased by the trustees of the British Museum, 

 and casts of the bones were taken. Among the various writings 

 by learned men on the subject, Professor Owen's masterly 

 description stands pre-eminent ; indeed, he was the only one to 

 solve the riddle, to thoroughly explain the structure of this 

 giant sloth, and to show how its food was obtained.^ Neither 

 Cuvier, nor the German doctors, nor Mr. Clift had succeeded in 

 so doing. 



In the Natural History Museum (Stand O, Gallery No. 2 on 

 plan) is a cast representing the animal nearly erect, and grasping 

 a tree. This magnificent cast (see Plate XVII.) represents an 

 animal eighteen feet in length, and its bones are more massive 

 than those of the elephant. For instance, the thigh-bone is nearly 

 thrice the thickness of the same bone in the largest of existing 

 elephants, the circumference being equal to the entire length. 

 To a comparative anatomist several striking indications of great 

 strength present themselves ; thus, not only the very forms of the 

 bones themselves mean strength, but their surfaces, ridges, and 

 crests are everywhere made rough for the firm attachment of 

 powerful muscles and tendons. In the fore part of the body the 

 skeleton is comparatively slender, but the hind quarters show 

 enormous strength and weight combined. The tail, also, is very 

 powerful and massive. The fore limbs are long, and evidently 

 constructed for the exertion of great force. How this force was 

 applied we shall see presently. In both sets of limbs we notice 



' His views are expounded in his Memoir on the Jllcgatherium, or Giant 

 Grotmd Sloth of America, i86l, which is beautifully illustrated. The Royal 

 Society gave /lOO (part of a Government grant of ;^iooo) to enable Professor 

 Owen to carry out this important work. 



