CHAPTER V 



THE SLOW-WORM, ANGUIS FRAGILIS — continued 

 REPRODUCTION SLOUGHING HIBERNATION ENEMIES. 



Reproduction. — Reproduction in lizards takes place 

 in one of two ways, either by the deposition of the 

 eggs by the mother when the eggs are but imperfectly 

 developed, or, secondly, by the bringing forth of the 

 young fully developed and able to look after them- 

 selves from birth. Both methods are found in British 

 species, that of the slow-worm being the latter method. 

 That is to say that Anguis fragilis is ovo-viviparous 

 or viviparous. The two terms are used synonymously, 

 but the former is the more descriptive, since it denotes 

 the additional fact that the young have been carried 

 to full time within an egg-membrane. The same 

 process obtains in the adder. The egg-membrane is a 

 very delicate transparent structure easily ruptured by 

 the embryo when fully developed. This generally 

 happens in August or September, the exact time 

 depending upon the nature of the season. In a warm 

 early spring the young slow-worms see the light in 



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