i62 THE INFANCY OF ANIMALS 



Some of the lizards and some tortoises lay as few as five, 

 some snakes lay one hundred, some turtles as many as two 

 hundred. Yet the most prolific species, as with the birds, 

 do not seem to outnumber those which lay but a few eggs. 

 It is possible, of course, that where a large number are 

 laid a considerable proportion are infertile. In the case 

 of the python, referred to earlier in this chapter, out of 

 one hundred eggs only half produced young, and some of 

 these soon died. Nevertheless about thirty-six survived, 

 which is a large number regarded as an annual output. 



Some idea of the relation between the number of eggs 

 and the mortality of the young is afforded in the case of 

 the South American " arrau turtle " (Podocnemis expansa), 

 one of the water-tortoises. This species lays its eggs, 

 about two hundred in number, on the sand-islands of the 

 Amazon and Orinoco and their tributaries, and as soon 

 as the young are hatched they are greedily snapped up 

 by crowds of jabiru storks, alligators and fishes, while the 

 adults fall a prey to the stealthy jaguar, which turns them 

 over on to their backs and neatly cleans out the shell with 

 his powerful claws. But the ravages of this host of what 

 we may call natural enemies are as nothing to the destruc- 

 tion wrought by man. 



The naturalist Bates, in his fascinating book " The 

 Naturahst on the River Amazon," gives us a long and 

 most interesting account of the way in which these eggs 

 were collected in his day. He was taken by the natives 

 to witness the egg-harvest, and describes this in most 

 vivid language. The " turtles " lay their eggs during the 

 night, and when Bates climbed the look-out, erected by 

 the natives for the purpose of observing the turtles without 

 disturbing them, he saw the sands black with the multi- 

 tudes scurrying back to the river. The collection of the 



