236 BRITAIN'S BIRDS AND THEIR NESTS. 



Carrion -Crow territory, connecting the part of western 

 Europe inhabited by the bird with its Asiatic area. 

 This cui'iously mixed distribution presents many problems, 

 among them the presence of the Black Crows that 

 occur in small numbers, as we have seen, as autumn 

 migrants on our eastern seaboard. 



In appearance the two Crows differ only in the gray 

 parts of the plumage of the Hoodie. The habits of 

 the two kinds are apparently identical, except in so far 

 as they are aiFected by the varying circumstances of their 

 respective areas. Thus, for instance, the nesting habits 

 are alike ; but rock-sites are necessarily more often used 

 by the Hoodie in the Highlands than by the Black 

 Crow in its more thickly wooded area. Sometimes the 

 Gray Crow is compelled to nest on the ground among 

 the heather, or in some other unusual place. In the 

 mild southern region of Ireland, also, the Hoodie is 

 some weeks earlier in its nesting operations. The eggs 

 of the Gray Crow are said to have a tendency to be 

 longer in shape and paler and brighter in colour than 

 the others, but the clutches are, as a rule, indistinguish- 

 able. The notes of the two Crows are thought to be 

 distinct by many who know both well. If the Carrion- 

 Crow's note be syllabled as a harsh 'corrr,' the Hoodie's 

 may be described as a more ' open ' ' caiTr.' Both are 

 quite distinct from the much less harsh ' cah ' or * caw ' 

 of the Rook, When all is said, there is practically no 

 great difference of any kind between the two Crows 

 except that of plumage coloration, and that is more 

 conspicuous than important. 



For this reason, and because the two kinds interbreed 

 freely on all their 'frontiers,' many deny their right to be 

 considered as separate species. They should, we are told, 

 be considered as mere colour 'phases.' To this, however, 



