ORDER SAURIA. I7I 



in the diagonal of a parallelogram, of which it may be con- 

 sidered to form the sides. 



The rectitude of direction in the walk is continually 

 changed in those lizards, in which the greater or less breadth 

 of the feet must be taken into consideration, and the variable 

 degree of separation in these parts, which permits them, in- 

 cludes a basis of sustentation of greater or less extent, or ac- 

 commodates itself more or less to the inequalities of the 

 soil. 



If these animals, although their limbs be of equal dimen- 

 sions, support with effort, on feet too small or too weak, a 

 heavy, thick, or overlong body, they then walk with slow- 

 ness, constraint, and embarrassment. Such is the case with 

 the crocodiles and chalcides. 



Some saurians leap with great agility, as, for instance, the 

 iguanas and tupinambis. 



Thus we find the movements of all the genera of saurians 

 contribute to enliven the scene of the animated world, either 

 amid the verdure of the earth, or on the bosom of the rapid 

 river, or the tranquil lake. The lizard, which seems almost 

 to swallow the ground in the rapidity of its course ; the fly- 

 ing dragon hovering from branch to branch, and shooting 

 into the air ; the dracaena, bathing in the limpid stream ; the 

 anguis (for after all it may be said to belong to this order) 

 gliding beneath the dry leaves and bushes ; the gavial, 

 cleaving the waves with the rapidity of an arrow, all present 

 in their varied and lively evolutions, some of the most inter- 

 esting spectacles in this sublunary world, where nothing 

 remains unmoved, and where the power and the marvels of 

 nature should excite our continual and unlimited admiration. 



We have already had occasion to hint that the organs of 

 sensation vary considerably in the four grand orders of the 

 reptile class. As for the saurians, they have as great a 

 number of senses as the best conformed animals among the 



