SEA SNAKES 93 



^ marking of alternate dark and light bands is very common in sea snakes, especially in young 

 individuals. The same coloration also occurs in many fishes, including the shark shown above, 

 and many eels. 



viper. As no snakes had been caught during the night, the only solution to 

 the mystery was that one of the original two must have given birth to three 

 young ones. At a first examination of the "young" this solution seemed 

 rather improbable. In the first place, they were nearly half as long as the 

 designated mother, and in the second, the coloration was quite different: 

 whereas the young had a handsome coloration with sharply defined dark 

 and light rings, the parents had a dark back and a light belly. Moreover, 

 the young made no impression of being newly born but behaved as 

 though they had lived a long life in the water. All these things, however, 

 are characteristic of sea snakes, and a closer inspection in fact proved 

 that the young snakes belonged to the same species as the big ones, so that 

 there can be little doubt that we had found the right solution. 



These features of young sea snakes show, perhaps better than any- 

 thing else, how well these creatures are adapted to an aquatic existence. 

 Not only do they bring forth living young (many land snakes do that), 

 but the young are born in a very advanced stage and with all the modifi- 

 cations found in the adult animal, so that they are immediately self-sup- 

 porting in the struggle for existence. An Indian zoologist, incidentally, 

 has recently shown that this advanced development is due to a trans- 

 mission of food from the mother to the embryo, a placenta being formed 

 round each egg as in mammals. If this were not the case, the young 



