158 



tree ; and what inhabitant of the forest more obnoxious to such an accident than 

 one destined by its organization to be habitually engaged in uprooting, and there- 

 fore in danger from the descent of heavy trees ? The form of the healed, as well 

 as of the partly-healed fracture, in both of which the fissures diverge from a 

 longitudinal, instead of radiating from a central depression, accords better with 

 a blow from a branch or trunk of a tree than with one inflicted by the point of a 

 large claw. It must, therefore, be conceded, that both the injuries, and the struc- 

 ture of the skull bv which their immediate fatal effects have been obviated, accord 

 with the habits assigned to the Megatherian animals in the present Memoir ; 

 while they can receive no elucidation from, nor appear in any way connected 

 with, the acts of digging the earth for roots, or ants, or for concealment, which 

 have been severally conjectured to be the habitual labour of the Megatherioids 

 by Cuvier, D'Alton, and De Blainville. 



It has been justly asked by Dr. Lund* in reference to the fossohal hypothesis 

 of the Megatherioid quadrupeds, "For what purpose should these monsters 

 have burrowed ? To protect tliemselves from fheir enemies ? Without alluding 

 to the length of time so bulky and helpless a creature must have required to 

 excavate a hole sufficient for its huge carcass, of what use could such a den be 

 for a refuge to an animal, whose food would, of necessity, often call it away?" 



The extreme form of the fossorial hypothesis proposed by MM. Pander and 

 D'Altonf, against which Dr. Lund's remarks are levelled, and which I have 

 shown that the organization of the Megatherioids confutes, can only find 

 favour with the naturalist who, conceiving the Megatherium to have been or- 

 ganized like the Armadillos, concludes that it had the same habits and mode of 

 life. The modified form of the same hypothesis, viz. that which interprets 

 the organization of the Megatherioids as being adapted to digging up the 

 soil for roots, the supposed food of these gigantic quadrupeds, has most pre- 

 vailed with Palaeontologists since Cuvier first propounded it ; and both from the 

 eminence and scientific caution of its author and from the arguments by which 

 this opinion has been supported, it cannot lightly or without due consideration 

 be set aside. 



In the first place it is to be observed that the only subterranean parts of 



* hoc. cit. p. 19. t See Note *, p. 10. 



