VIVirAROUS LIZARD. 37 



Continent its range does not appear to be very extensive : 

 it is not found in Italy, nor, I believe, in France, and is 

 very probably confined in a great measure to our own 

 latitude. Its movements are beautifully graceful as well 

 as rapid; it comes out of its hiding-place during the warm 

 parts of the day from the early spring till autumn has far 

 advanced, basking in the sun, and turning its head with a 

 sudden motion the instant that an insect comes within its 

 view, and darting like lightning upon its prey, it seizes it 

 with its little sharp teeth and speedily swallows it. Thus 

 it will often take a great number of the smaller insects, 

 preferring those of the dipterous order; though it will not 

 refuse many of the coleoptera or orthoptera, if they be not 

 too large. 



Instead of depositing her eggs in the sand to be hatched 

 by the warmth of the sun, as is the case with the former, 

 the female of the present species retains the eggs within 

 the oviduct until the young are ready to leave them, and 

 thus they are produced alive. As in all the ovo-vivipa- 

 rous reptiles, the covering of the egg is very thin, and 

 merely membranous. In this respect they differ from 

 those which deposit their eggs before the embryo is formed. 

 In the latter case a more efficient protection is necessary, 

 and the covering is either calcareous, as in the Tortoises 

 and Crocodiles, or of a substance resembling parchment, as 

 those of the Snakes and most Lizards. In the Viper, 

 which also produces its young alive, the covering, as in the 

 present animal, is extremely thin and very easily torn ; 

 and there is reason to believe that the laceration of this 

 membrane and the emancipation of the young take place 

 in and are occasioned by the very act of parturition. 



As the young ones are occasionally found with the 

 mother, there is some reason to believe that these little 



