222 EGGS OF BIRDS. 



and unskilful operations of the picker and dresser. 

 No, let the parental duties cease; and when the 

 bird retires to its maritime downs, if doomed to 

 suffer, the individual dies alone, and no starving 

 broods perish with it. I supplicate from the youth- 

 ful sportsman his consideration for these most in- 

 nocent creatures, the summer wheatear and the 

 swallow. 



The eggs produced by the wheatear are uniform 

 in colour and similar in shape ; but the eggs of 

 birds in general vary much, and are occasionally 

 very puzzling to identify, when detached from their 

 nests, as the colourings and markings differ greatly 

 in the same species, and even nest. Those of one 

 colour, like this wheatear's, retain it, with only 

 shades of variation ; but when there are blotchings 

 or spots, these are at times very dissimilar, occa- 

 sioned, in great measure, probably by the age of 

 the bird ; though this cannot account for the differ- 

 ence of those in an individual nest. None vary 

 more than the eggs of the common sparrow. Those 

 of marine birds, especially the guillemot (colymbus 

 troile), are often so unlike each other, that it re- 

 quires considerable practice to arrange them. The 

 plumage of birds has probably never varied, but 

 remains at this hour what it originally was : but 

 whether these markings on the eggs have any con- 

 nexion with the shadings on the feathers, it is diffi- 

 cult to determine ; as we know that eggs entirely 

 white will produce birds with a variety of plum- 

 age. The shell of the egg appears to be designed 



