GENERATION OF BOA. 323 



they knew that this Boa produced its young from 

 eggs. 



*' Is this to be received as a case of Snakes that 

 retire upon alarm into the mouth and stomach of the 

 parent ? It is stated of the Rattlesnake in Hunter's 

 ' Memoirs of a Captivity among the North American 

 Indians,' that * w^hen alarmed, the young ones, which 

 are generally eight or ten in number, retreat into 

 the mouth of the parent, and reappear on its giving 

 a contractile muscular token that the danger is 

 past.' Credible eye-witnesses say the same of the 

 European Viper. (See Charlesworth's Mag. Nat. 

 Hist. vol. i. new series, 1837. p. 441.)" 



In a recent communication to me, Mr. Hill de- 

 scribes the Yellow Snake as viviparous, on the au- 

 thority of a young friend studious of natural history. 

 A gravid female of this species, taken by him, brought 

 forth, after some days, eleven young Yellow Snakes. 

 If there was no error in the observation of this case, 

 it must be considered as an aberration of habit. The 

 generation of the BoadcB is well known to be ovi- 

 parous, and the fact above mentioned as having fallen 

 under my own notice, proves that, sometimes at least, 

 our Chilahothrus produces eggs. Is it possible that 

 a Serpent, normally oviparous, might retain the eggs 

 within the oviduct until the birth of the young, 

 when circumstances were not propitious for their 

 deposition ? 



The scaly armour of this Serpent does not protect 

 it from the attacks of parasitic insects. I found one 

 infested by a fiat Tick {Ixodes), in some numbers, 



