300 REPTILES. 



class are scaly and cold-blooded ; and that they reproduce 

 their species in one of two ways, either laying eggs much 

 like birds, or else hatching the egg within their own 

 bodies, and bringing forth the young in the perfect state, 

 — a birth which must, however, be regarded as distinct 

 from that of the mammal. 



One of the most remarkable functions in reptiles is the 

 periodic casting of the loose skin or slough, which comes 

 away entire, — a performance which, in some 



cases, involves considerable rubbing against 

 any convenient stone or other hard substance. In birds, 

 which may be considered as modified reptiles, w^e call the 

 process "moulting." After this change the new undercoat 

 is very bright ; and the reptile, more especially a snake, is 

 at this time particularly susceptible to cold. I never went 

 so near to losing a 6-foot constrictor that I was bringing 

 home from Australia as after it had cast its slough piece- 

 meal (which is by some considered a sign of bad condition) 

 while we were crossing the Timor Sea. It pulled through, 

 however, and died recently at the Zoo. Dr Stradling, 

 who kindly read this portion of my proof, tells me that 

 young snakes usually cast the slough entire, wdiereas old 

 snakes rarely do so, quite independent of the condition 

 they are in at the time. Lizards are generally credited 

 with the power of reproducing any limb which they lose, 



more particularly the tail, which frequently 

 fT'^^"^ ^°^ comes away when a lizard is roughly handled. 



Miss Hopley^ criticises this, however, and is 

 of opinion that the reproduction of the tip of the tail is 

 a very imperfect performance. It is commonly stated 

 that there are no reptiles in Ireland. This is a mistake, 

 as although there are no snakes there, — it is interesting 

 that zoologists should have failed hitherto in finding a 

 creditable explanation of their absence from a soil and 

 climate apparently suited to their requirements, — lizards 

 are abundant. 



1 British Reptiles, p. 83. 



