74 REPTILES 



maximum number produced by different species of the latter is 

 still required. In 1906 I received the skin of a female of the 

 beautifully-coloured Gabun viper, or puff-adder {Bitis gabonica), 

 together with several young ones taken from the body when 

 the. reptile was killed. These young ones measured about 

 twelve inches in length, and the total number was said to be 

 thirty. Thirty feet of young snakes is certainly a goodly- 

 family, and confirms current statements as to the abundance of 

 these deadly reptiles in the forests of equatorial Africa. The 

 number of young produced at a birth by adult females of the 

 European viper is stated to be generally from twelve to fourteen 

 although, occasionally reaching sixteen. Younger females, how- 

 ever, produce only five or six at a time. 



The North American banded water-snake (Tropidouotus 

 fasciatus) seems to be an unusually prolific species, a female 

 in the New York Zoological Gardens having on one occasion 

 given birth to sixty-two young — a family so numerous that if 

 literally overran the cage in a mass of writhing brilliantly 

 coloured bodies. 



Usually, it seems, the eggs of reptiles are hatched within 

 comparatively few weeks of being laid. A remarkable excep- 

 tion is, however, afforded in the case of the New Zealand 

 tuatera, which is in so many ways strange and aberrant. 

 Although the eggs are laid during the summer (of the southern 

 hemisphere), that is to say, from November till January or 

 February, and contain fully developed embryos by the follow- 

 ing August, they are not hatched till about thirteen months 

 after being laid, thus coming into the world in summer. 

 During the period of delayed development the embryos appear 

 to undergo a kind of hibernation ; the cavity of the nose 

 becoming blocked by a growth of tissue which is absorbed as 

 the time of hatching approaches. The eggs are not laid in the 

 tuatera's burrow but in a warm sandy spot, where they may 

 receive the full advantage of the sun's rays. 



