292 THE STORY OF THE BIRDS 



lay on an average five or six ; some of the Coracii- 

 formes, such as the Kingfisher, and some Wood- 

 peckers, lay six or eight ; whilst amongst the 

 most numerous egg-producers we must include 

 the Game Birds, some of the Rails and the 

 Ducks, their clutches varying, roughly speaking, 

 from ten to twenty or even more. The number 

 of eggs that a bird may lay is no indication of 

 its relative abundance. The Fulmar was com- 

 puted by Darwin to be the most numerous bird 

 in the world, and yet it lays but a single egg. 

 The Gannet, the Guillemot, and the Puffin exist 

 in countless hordes in northern latitudes, yet 

 all of them lay one egg only. On the other 

 hand, species that produce an exceptional 

 number of eggs are not proportionately nume- 

 rous. A possible explanation of the phenome- 

 non may be that the species producing the 

 fewest eggs are least exposed to decimating 

 influences, whilst those that lay an exceptionally 

 large number may be more liable to the attacks 

 of certain enemies. 



The colours of eggs are to a certain extent 

 characteristic of the various orders, families, and 

 even genera, which, on the theory of evolution, 

 is only what we might expect to find. As a rule 

 the more closely allied the species the greater will 



