142 STORY OP THE REPTILES 



with most fishes and some amphibians. In shape 

 they are all longer than thick, with both ends equally- 

 rounded, but a few turtles' eggs are almost as globu- 

 lar as a boy's marble. In no case are they pointed 

 more at one end than the other, and, so far as known, 

 they have never possessed such special colors as are 

 found in those of birds. 



In nesting, tortoise-forms bury their eggs under 

 sand — scraping a place and covering them. The 

 rule is that the mother takes no further care of her 

 young. The sun's heat alone hatches them. 



In the crocodilians it is said that there is some 

 watching of the buried eggs; and the mother digs 

 her young out when hatched, leads them to the 

 water, fights the male away, who would eat them, it is 

 said, and in some cases she ejects food from her own 

 stomach to feed them. Some of this order dig deep 

 holes and put trash or litter of vegetable substances 

 in with their eggs and then cover all .over. It is 

 claimed by some students that this procedure is for 

 the purpose of getting additional heat by the hot-bed 

 effect of the rotting litter ; by others, that it is in- 

 tended merely to cushion or protect the eggg— per- 

 haps a sort of nest-building instinct. Certain it is 

 that some low birds bury their eggs in almost ex- 

 actly the same manner, and that others of the same 

 order heap up a great mass of brush, grass, etc., and 

 lay their eggs in this, where they are hatched either 

 by the heat of decay or by that of the sun. 



One large poisonous snake of Asia is said to make 

 a nest of a heap of rubbish, and to defend it — even 



