586 SNAKES. 



adhering to its tail, when a boy drew attention to it, saying, 

 ' Papa, that snake is all ragged and torn on its tail' 



'Yes, my dear, it is casting its tail' Papa must have been 

 reading Aristotle, who wrote : ' Tails, also, of serpents and 

 lizards when cut off are reproduced.' With regard to the 

 reproduction of their eyes, Aristotle spake more cautiously. 

 ' It is reported that the eyes of serpents, if dug out, will be 

 reproduced.' But, on the contrary, the eyes of snakes are 

 easily injured, and not easily healed ; snakes are therefore 

 frequently seen partially blind. As need scarcely be said, 

 only lizards 'reproduce' a tail that has been accidentally 

 abridged ; and the repair is after all only a boneless one. 

 The truncated member gradually heals, and by and by a 

 short point is again formed, but can always be recognised as a 

 repaired, and not the original, tail ; and as far as I have been 

 able to observe, viz. for three or four months, no bone was 

 reproduced. Probably also a snake's tail might heal in the 

 same way, and to a casual observer appear quite perfect ; 

 but the anatomical structure in either case would not, I 

 imagine, be restored. 



That boy was not far wrong when he said he thought the 

 python did not know which w^as its own tail. At all events, 

 it is not endowed with much external sensation, as one might 

 judge by the way in which the rats and guinea-pigs take 

 liberties with it. This must be owing to the thickness of the 

 cuticle, because, as we have seen in the constricting snakes, 

 there is keen muscular sensibility in the tail. I may cite an 

 instance of each case. One day a young rabbit caught hold 

 of a small python with its teeth and held firmly on. The 

 reptile was moving across the cage, and did not appear to feel 



