SKELETON OF CROCODILE. 3 



With the exception of the tortoises, the Eeptiles mostly possess a gooaly array of 

 teeth, set in the jaw or palate, and as a general fact, being sharp and more or less curved 

 backward. Their bodies are covered with various modifications of the structure termed 

 the dermal, i.e. skin skeleton, and are furnished with scales and plates of different forms. 

 In some cases the scales lie overlapping each other like those of the fish, in others they 

 are modified into knobby plates, and in some, of which the tortoises afford well-known 

 examples, they form large flat plates on the back and breast, and scales upon the feet 



and legs. 



The young of Reptiles are produced from eggs, mostly being hatched after .they have 

 been laid, but in some cases the young escape from the eggs before they make their 

 appearance in the world. As a general fact, however, the eggs of Reptiles are placed in 

 some convenient spot, where they are hatched by the heat of the sun. Some species are 



SKELETON OP CROCODILE 



very jealous about their eggs, keeping a strict watch over them, and several of the larger 

 serpents have a curious fashion of laying the eggs in a heap, and then coiling themselves 

 around them in a great hollow cone. The size of the eggs is extremely variable, for, 

 although as a general fact those of the smaller Reptiles are large in proportion to the 

 dimensions of the parent, those of the crocodiles and alligators are wonderfully small, not 

 larger than those of our domestic geese, and in many cases much smaller. They are 

 usually of a dull white colour, and in some instances are without a brittle shell, their 

 covering being of a tough leathery consistence. 



In form, and often in colour, the Reptiles exhibit an inexhaustible variety, and even 

 each order displays a diversity of outward aspect unexampled in the two previous classes 

 of Mammals and Birds. Strange, grotesque, and oftentimes most repulsive in appearance, 

 though sometimes adorned with the brightest tints, the Reptiles excite an instinctive 

 repugnance in the human breast ; and whether it be a lizard, a snake, or a tortoise, the 

 sudden and unsuspected contact of one of these beings will cause even the most 

 habituated to recoil from its cold touch. This antipathy may, perhaps, have some con- 

 nexion with the instinctive association of cold with death ; but whatever may be the 

 cause, the feeling is deep and universal. 



