REMARKABLE POISON GLANDS. 239 



and become very tame, and, moreover, unlike most other snakes, 

 they will feed very freely. I have kept several for many years, 

 some of which have grown considerably since their capture. 

 They are fed upon frogs and toads. 



There is always great danger of treading upon and getting 

 bitten by Night Adders, because they are very sluggish, and do not 

 make much effort to get out of the way, often preferring to lie 

 quiet, seeking to escape observation by that means. The danger 

 is increased by their habit of lying across pathways, their colour 

 harmonising with that of the ground. They are termed Night 

 Adders because they usually issue forth from their lairs about 

 dusk. 



Although belonging to the Viper family, the Night Adders 

 are oviparous ; that is, they lay eggs. Those I have kept in 

 captivity laid batches of eggs varying in number from a dozen to 

 twenty-five, during the summer months. None of the eggs 

 showed any signs of incubation. The parent in most instances 

 coiled round her eggs and remained there several days, but 

 eventually abandoned them owing to being repeatedly disturbed 

 by the other snakes, and the attendant who cleaned out the cage 

 and renewed the water in the water-vessel. In nearly every case 

 the parent showed the desire to incubate the eggs, and from this 

 I infer they often remain coiled round the eggs, until they are 

 incubated, in the wild state. The eggs of snakes can easily be 

 hatched by placing them in damp earth and putting them in a 

 chicken incubator. A farmer gave me some Night Adder eggs 

 which he ploughed up in a field. I placed them in a box of damp 

 earth and dead leaves and left them out in the sun. In a month's 

 time they hatched out. These, however, were partly incubated 

 before I received them. Snakes' eggs take from two to three 

 months to hatch according to the degree of incubation which 

 has taken place before the eggs are laid. 



In the " Cambridge Natural History on Amphibia and 

 Reptiles," by Gadow, page 638, there is the following : "All 

 the Viperidae are very poisonous, and all except the African 

 Atractaspis are viviparous." 



Fa5n:er, in his " Thanatophidia of India " says : " All the 

 Viper family of snakes, as their name imphes, are viviparous." 



The Atractaspis snakes, viz. the Oviparous Adder and Duerden's 

 Adder, lay eggs, but the Night Adder {Causus rhombeatus) does 



