CROWS. 



527 





as intneatc as that of the red-shafted and 

 yellow-sliafted Hickers of our contiiient. 

 The carrion-crow is entirely black ; the 

 hooded-crow is trray, with the head, tlimat, 

 wing, and tail lilack. The former iidiabits 

 in Europe the southern parts, while the 

 hooded-crow is northern and eastern ; but 

 the areas of both overlap, and in tliose dis- 

 tricts innumerable intermediate specimens 

 occur. Hybridization easily accounts for 

 these, inasmuch as the interbreeding of typi- 

 cal birds of both species is an established 

 fact. But that was not the greatest dith- 

 culty which )>resented itself in the apparent- 

 ly western carrion-crow coming to light again 

 in eastern Siberia, to the east of the hooded 

 species. Scebohm has attempted to show 

 that the true e\]ilanation is that the black 

 one is originally an eastern species, which 

 has invaded southern Enrojie, establishing 



a western colony there after having crossed the area inhabited by its gray cousin. To 

 me the problem seems even easier; for I think it ]iossiliIe to sejiarate the east Asiatic 

 birds, at least subspeciiically, from the Eurojieau form. 



Fio. 2C0. — Crocitia erylhrorhynchut, red-billed jay. 



