THE CLASS REPTILIA. 5 



venomous. Even these three are confined to England, 

 Scotland, and Wales, there being no representative 

 of the serpent tribe indigenous to Ireland — another 

 grievance from the naturalist's point of view, per- 

 haps ! St Patrick's decree of banishment has long been 

 popularly associated with this curious local immunity, 

 while others have suggested that the fact points to 

 Ireland having been cut off from the continent of 

 Europe before the serpent species had reached so far 

 west. Whatever the real explanation may be, the 

 fact remains that (with the exception of some isolated 

 occurrences referred to later) Ireland has no serpents. 

 Lizards are the only reptiles found there. 



New Zealand, too, has no serpents except venomous 

 sea-snakes, though here a^ain the order of lizards is 

 represented ; and there are other oceanic islands which 

 exhibit a similar peculiarity. 



Climate has, of course, a great deal to do with the 

 distribution of reptiles, as they are essentially in- 

 habitants of warm and temperate lands, becoming 

 rarer the farther north one goes. Thus, " In Europe 

 snakes cease at 60° north latitude, and at G000 feet 

 elevation in the Alps " ; * the lizards, however, ex- 

 tend both to the more northern latitudes and to 

 higher elevations, except in North America, where 

 the serpents are found more northerly than the 

 lizards. 



To the naturalist who studies the development of 



1 Packard. 



