OF A FORMER WORLD. 31 



within its reach. It may, perhaps, have lurked in shoal 

 water along the coast, concealed among the sea-weed, and 

 raising its nostrils to the surface from a considerable depth, 

 have found a secure retreat from the assaults of dangerous 

 enemies, while the length and flexibility of its neck may 

 have compensated for the want of strength in its jaws, and 

 its incapacity for swift motion through the water, by the 

 suddenness and agility of the attack which they enabled it 

 to make on every animal fitted for its prey wluch came within 

 reach." 



Megalosaurus.* Remains of this crocodelian have been 

 found in the oolite at Stonesfield, in Oxfordshire, and at Be- 

 sancon, and also by Dr. Mantell, in the Wealden of Til- 

 gate forest. From the size and nature of the bones found, 

 Cuvier considered the animal as partaking of the structure 

 of the moniter and crocodile, and to have been from forty to 

 fifty feet in length. The femur and tibia measure nearly 

 three feet each, so that the hind leg must have been about 

 six feet long. The thigh and leg bones of crocodiles, and 

 other aquatic quadrupeds, are solid throughout, but those of 

 the Megalosaurus were hollow, like those of land quadru- 

 peds, an arrangement by which both lightness and strength 

 are secured. It is therefore conjectured, that the Saurian, 

 under consideration, lived chiefly on land. The structure 

 of its serrated teeth indicate it to have been carnivorous. 



Fig. 3. 



Anterior extremity of the right lower jaw of Megalosaurus in side 

 view one fourth of nat. size. 



' From /ueyaf , great, and aai>QO , a lizard. 



