ORDER SPURIA. 179 



time, either in an entire piece, like a sheath, or in dry, horny 

 and colourless scales. Many of them, besides, have their toes 

 joined so that they cannot be applied but with difficulty to 

 the surface of bodies ; and though some others have them 

 very long, and separated from each other, yet the under part 

 is furnished with such thick scales, that a very small degree 

 of sensibility must be left in it. 



The corpus mucosum, under the epidermis of the saurians, 

 is very livelily and variously coloured. There is great 

 tenacity in the dermis, which is closely adherent to the mus- 

 cles, and variable in thickness. 



In many species may be observed, under each thigh, a 

 very regular range of small pores, from which a viscous 

 humour exudes. This peculiarity belongs to all the genuine 

 lizards. 



The saurian reptiles live generally on small quadrupeds, 

 birds, mollusca, worms, and insects. They never drink. 

 Their digestion is remarkably slow, and they eat but seldom, 

 especially during the cold season. If some among them, 

 such as the crocodiles, make a considerable consumption of 

 food, it must be attributed to the immense bulk which they 

 have to support. One repast, however, will suffice tliem for 

 many days. 



From a necessary consequence of defective mastication in 

 these animals, the salivary glands should constitute a less 

 important apparatus in their organization than in that of the 

 mammifera. In some of them the tongue is composed in a 

 great measure of a thick glandulous mass, formed by a 

 number of small tubes united by their base, and separated 

 towards the surface of the organ. These constitute so many 

 papillae, which render the surface somewhat bristly when 

 they are fine. The sides of the mass are pierced witli a 

 multitude of small holes, which give passage to a humour 

 secreted by the gland itself. This disposition is particularly 



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