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CHAPTER III. 



THE ORDER OF LIZARDS.— SAURIANS. 



This is the second order of the great section of scaly reptiles' 

 (Squamata), as distinguished from the shielded reptiles {Cata- 

 phracta). The name Saurian, 5aupos, given by Aristotle to the genus 

 of lizards, has been more comprehensively applied to a group 

 of reptiles which have the body elongated, covered with scales, or 

 having the skin rough like shagreen. They have, for the most 

 part, four feet, the toes of which are furnished with hooked claws ; 

 the eyelids are movable, and their jaws armed with encased teeth ; 

 they have a distinct tympanum, a heart with two auricles and a 

 single ventricle, sometimes partially valved, having sides and a 

 sternum. They are not subject to metamorphosis, and, finally, 

 they are furnished with a tail. 



[" By far the greater number of the Saurians," writes Dr. 

 Gunther, "are easily distinguished from the other orders of 

 Reptiles by their elongated form, by their movable thorax covered 

 with skin, by the presence of legs, and by their general integu- 

 ments, which are either folded into scales, or granular, or 

 tubercular, or shielded ; still, there are many Saurians which, at 

 a superficial glance, might easily be taken for members of the 

 preceding order, that of the Snakes ; and it cannot be denied 

 that there is a gradual transition from one of these orders to the 

 other. On the part of the Saurians, we allude to those which 

 have no externally visible limbs, and which combine with a 

 greatly elongated, cylindrical body, the peculiar kind of locomo- 

 tion we observe in Snakes. Yet the greater affinity of these 

 Reptiles to the ordinary Lizards is indicated by another character, 

 which is in intimate connection with their mode of life. The 

 Snakes, having movable maxillary bones, and mandibles not joined 

 by a symphidis, are enabled to swallow other animals of appa- 

 rently greater bulk than their own. In the Saurians the maxillae 

 are fixed and immovable, and the mandibles are joined by an 



