434 THE WONDERS OF GEOLOGY. Lect. IV. 



largest existing saurians, renders it vain to attempt the re- 

 storation of the form of this colossal reptile, till the skull, 

 jaws, &c. are known. In all probability the entire or a 

 considerable portion of the skeleton of a young Iguanodon, 

 will sooner or later be brought to light, and yield the 

 information necessary to enable the palaeontologist to re- 

 construct the skeleton, and delineate the physiognomy 

 of the living original. 



In the present state of our knowledge we may, however, 

 safely infer, that the body of the Iguanodon was equal 

 in magnitude to that of the Elephant, and as massive in its 

 proportions ; for, being a vegetable feeder, a large develop- 

 ment of the abdominal region may be inferred. Its limbs 

 must have been of a proportionate size to sustain so enor- 

 mous a bulk ; one of the thigh-bones (in the British Museum), 

 if covered with muscles and integuments of suitable propor- 

 tions, would form a limb seven feet in circumference. The 

 hinder extremities, in all probability, presented the unwieldy 

 contour of those of the hippopotamus or rhinoceros, and 

 were supported by very strong short feet, the toes of 

 which were armed with claws like those of certain tur- 

 tles. The fore-legs appear to have been less bulky, and 

 were furnished with hooked claws resembling the ungueal 

 phalanges of the Iguana. The teeth demonstrate the 

 nature of the food required for the support of this herbivo- 

 rous reptile, and the power of mastication it enjoyed ; and 

 the ferns, cycadeous plants, and coniferous trees, with 

 which its remains are associated, indicate the flora adapted 

 for its sustenance. But the physiognomy of this creature, 

 from the peculiar modification of the skull and jaws, re- 

 quired for the attachment and support of the powerful 

 muscles necessary for the trituration of tough vegetable 

 substances, must have differed entirely from that of all 

 known saurians. 



The length of the Iguanodon has been variously estimated ; 



! 



