108 GRALLJE. 



sexes in each of the two states, gave a semblance of truth to 

 the mistake. The young have the plumage on the upper 

 part grey, with yellowish brown spots, and have thence been 

 called grey plovers ; the winter plumage of the old birds is 

 often brown and yellow on the upper part, in which state 

 they are golden plovers ; and when they are in the prime of 

 their summer plumage, which they do not recover till they 

 are on the breeding grounds, they are black (or dusky) and 

 green on the upper part, with black on the breast, in which 

 state they are green plovers, although that name has been 

 sometimes given to the lapwing. 



Plovers are usually described as among those birds that are 

 subject to two moults in the course of the year, one in the 

 spring and one in the autumn, as at those times they change 

 their colours. With respect to resident birds especially, 

 this is a subject which demands the greatest caution, even 

 though, as is the case with plovers, the birds should resort to 

 lower and warmer parts of the country during winter. Birds 

 in confinement, that, have no labour to undergo in search of 

 their food, do moult extensively at certain periods ; but that 

 the same always takes place to the same extent in free birds, 

 is assumed rather than proved. 



On the subject of moults, changes in the colours of plu- 

 mage, and all those differences in the appearances of birds 

 which we have reason to ascribe to seasonal rather than to 

 sexual causes, we are always in danger of carrying our gene- 

 ralizations too far, and applying the known causes to explain 

 the new cases, without due attention to the differences of 

 climate, latitude, and other circumstances, which must have 

 an influence upon the result. 



Analogy drawn from any other class of organized beings, 

 cannot be conclusive proof, or even good argument, as applied 

 to birds ; but, on the other hand, there are general analogies 

 arising from the climates and seasons x>f the different lati- 



