434 

 BREEDING HABITS OF SOME SNAKES AND LIZARDS. 



BY 



Rev. F. Dreckmann, S.J. 



The name viper was originally applied to all poisonous snakes 

 under the idea that this class was distinguished by its viviparous 

 habits ; this idea has long been found to be erroneous as all the 

 poisonous eolubrine land-snakes, the cobra, krait, &c., are, as far as 

 we know, truly oviparous, and on the other hand the eolubrine 

 water-snakes, whether poisonous or not, are viviparous ; many of 

 them inhabit the open sea and it would not be easy for them to find 

 a place where they could safely deposit their eggs. Those poisonous 

 snakes, however, which belong to the now restricted order of 

 "vipers" — viperida? — were still considered to deserve their name 

 and to be without exception viviparous, but of late their claim to this 

 distinction has also become more than doubtful. 



In 1904 we received a note from the Rev. G. A. Miller, of St. 

 Joseph's College, Darjeeling (c.f. Journal, B. N. H. S., XV, page 

 729), in which he informed us that he had received a number of eggs 

 which on being hatched turned out to be eggs of Lachesis monticola; 

 from two of them the young ones issued whilst they were under 

 observation. The Rev. gentleman was kind enough to send us one 

 of the young ones together with the shell from which it had escaped, 

 and one of the eggs cut open with the fully developed embryo 

 inside : both are undoubtedly L. monticola, one of the Crotalidce or 

 pit-vipers. The Editors of our journal added the remark : " We 

 now possess the important evidence that this viperine snake is 

 oviparous." Its very close ally, however, L. gramineus — a common 

 snake of our ghauts — is certainly viviparous ; for this I have very 

 good evidence as one of them gave birth to a healthy family of fully 

 developed live young ones whilst I held it in my hand. 



At our last meeting Col. Bannerman showed us two very interest- 

 ing exhibits. One of them was a cluster of eggs laid by a Russell's 

 viper in captivity and the other one a batch of young ones born alive 

 by another snake of the same species. Here we have incontestable 

 evidence of the same snake — a typical viper — being both oviparous 

 and viviparous. It appears from these facts that a snake being 

 oviparous or viviparous cannot any more be considered as a generic 



