THE SNAKES OE EUROPE 



INTRODUCTION 

 CHAPTER I 



DEFINITION AND CLASSIFICATION 



SNAKES, Ophidia— regarded by some authorities 

 as an order of the class Reptilia, by the author 

 as a sub-order of the order Squamata, which includes 

 besides the Lizards, Lacertilia, the Chameleons, 

 Rhiptoglossa, and the extinct Dolichosauria and 

 Mosasauria — may be defined as greatly elongate 

 scaly Reptiles without limbs, or with mere vestiges 

 of the hind pair, without movable eyelids, without 

 ear-opening, with elongate, deeply forked tongue 

 retractile into a basal sheath, with transverse vent 

 and paired copulatory organs, and with the two 

 halves of the lower jaw independently movable, 

 connected at the symphysis by an elastic ligament. 



The latter character alone distinguishes them 

 from all Lizards, but no single Lizard possesses all 

 the others in combination. 



In their most highly developed form these Reptiles 

 are adapted for rapid reptation and for swallowing 



