CHAPTER VIII 



THEIR REPRODUCTION (EGGS) 



Eggs The development of the shell The deposition of the 

 colour pigments The shape of the markings How 

 formed The two types of markings Their distribution 

 General resemblances amongst eggs of the same 

 species Exceptions Composition of the colour pig- 

 ments The incubation of the egg Incubation periods 

 in the various avine orders The incubating sex The 

 texture or grain of the egg-shell The colour of the 

 interior of the shell The form of eggs The size of 

 eggs The number of eggs produced by species in the 

 various groups The colours of eggs Generic types of 

 eggs Variation in the colour of eggs in the same 

 species Of the Guillemot Of the Cuckoo Uniformity 

 of colour in other groups The colours of eggs heredi- 

 tary Eggs of hybrids The ancestral colour of eggs 

 The utility of colour White eggs in covered nests In 

 open nests Spotted eggs in open nests In covered 

 nests The protective colouration of newly hatched 

 birds. 



FOR centuries the Eggs of birds have attracted 

 the attention of the scientific naturalist ; and 

 there can be little doubt that they have been the 

 coveted spoil of the less learned perhaps from 

 an even earlier period still. To most people 



their central attraction is their great beauty and 



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