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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