146 CHILDHOOD OF ANIMALS 



seem to be on the way to protect the eggs by retaining them in 

 the body until they hatch, and many of them have actually become 

 viviparous. Amongst these are the smooth snake, the common 

 adder, most of the burrowing snakes and many of the sea snakes. 

 In viviparous eggs the shell is extremely thin. It is probably the 

 viviparous habit that has led to the belief that the adder opens her 

 mouth and receives her young into it when danger comes near. 

 Certainly the adder remains with and protects her young after they 

 are born, and the sudden disappearance of mother and young when 

 any one approaches is the starting-point of the notion. It has 

 been apparently confirmed by dissection, for if a gravid snake be 

 opened, her young, active and wriggling, may be found far forward 

 in the body, in a tube which is really part of the oviduct, but which 

 one not well acquainted with anatomy might easily take to belong 

 to the alimentary canal. The sea snakes are said to protect their 

 young after hatching, but maternal care in most snakes does not go 

 beyond finding a suitable locality for the eggs, which are usually 

 laid in heaps of earth and leaves, in holes, or in manure heaps. 

 The boas and pythons and some of the venomous snakes dispose 

 the coils of the body round the eggs and lie with them until hatching 

 takes place. 



Thus in fishes, batrachians and the different kinds of reptiles, 

 there are to be found all stages in the process by which the number 

 of the family is reduced, and better protection given to the eggs, 

 larvae and young. Prolificness is replaced by parental care, and 

 although there is little or nothing that can be thought of as educa- 

 tion, the instincts of both parents and young are modified by the 

 association in family life. 



