IGUANODON. 249 
consumption. And we must estimate the works 
of nature by a different standard from that which 
we apply to the productions of human art, if 
we can view such examples of mechanical con- 
trivance, united with so much economy of ex- 
penditure, and with such anticipated adaptations 
to varying conditions in their application, with- 
out feeling a profound conviction that all this 
adjustment has resulted from design and high 
intelligence. 
SECTION XI. 
AMPHIBIOUS SAURIANS ALLIED TO CROCODILES. 
The fossil reptiles of the Crocodilean family do 
not deviate sufficiently from living genera, to 
require any description of peculiar and discon- 
tinued contrivances, like those we have seen in 
the Ichthyosaurus, Plesiosaurus, and Pterodac- 
tyle; but their occurrence in a fossil state is of 
high importance, as it shows that whilst many 
forms of vertebrated animals have one after ano- 
ther been created, and become extinct, during 
the successive geological changes of the surface 
of our globe ; there are others which have sur- 
