424 M. Lund on Fossil Mammifera discovered in Brazil, 



latter bone which by its anomalous conformation produces the con- 

 tortion of the plane of all the rest of the foot. 



The molars, to the number of 5 above and 4 below, are not fur- 

 nished with roots as in the animals of the order of Edentata ; thus 

 differing from those of the Megatherium, which are described as 

 having two roots. 



The species of Megalonyx were provided with an excessively strong 

 tail, and probably prehensile, which together with the contortion of 

 the plane of the hinder feet and the enormous length of the claws, 

 must lead to the belief, observes M. Lund, that these animals, not- 

 withstanding the great weight of their body, were destined to climb, 

 like their representatives in the present creation. 



This genus appears to have been very rich in species ; M. Lund 

 already distinguishes five ; one of them, M. Cuvierii, was of the size of 

 a large ox, and this was not the largest species. 



A new genus would arrange itself by the side of Megalonyx, under 

 the name of Sphenodon, which was of the size of a hog. 



A new genus, designated by M. Lund by the name of Cydodon, and 

 containing one species, would come still closer to the Bradypoda. 



Returning to the animals above enumerated, and which are com- 

 prised in Cuvier's order Edentata, M. Lund observes: 1. That the 

 family of the Myrmecophaga, that of the Dasypoda, and that of the 

 Bradypoda, which, at the present period, are peculiar to America, also 

 existed there at the preceding epoch. 2. That at that period these 

 families were peculiar to this portion of the globe exclusively, as 

 they are at present, and the cause of this opinion is that no species 

 of these three families has been hitherto discovered in the diluvian 

 deposits of other portions of the earth. 3. TJiat this large order of 

 Edentata was at that time more numerous both in genera and spe- 

 cies than at the present day. 4. That most of these mammiferous 

 genera which formerly inhabited the country have disappeared. 

 5. That all then existing species have been destroyed, only two 

 species presenting some affinity, but not a perfect identity with living 

 species. 6. And lastly, that the animals of this order at this period 

 attained dimensions far more considerable than at present occurring. 

 The family of the Bradypoda have disappeared entirely from the 

 basin of the Rio das Velhas, which would be accounted for by the 

 absence of primaeval forests, all the country being occupied by that 

 form of vegetation termed by the Brazilians Campos. It is probable 

 that at the period during which these large animals lived it was 

 quite different, and that the country was then covered with immense 

 forests : still, however, everything leads us to suppose that they led 

 the same kind of life as their representatives of the present period. 



