4 o ANNALS OF BIRD LIFE. 



here to breed every summer. All these birds of 

 prey are regular migrants to Northern and 

 Central Europe, and winter in the basin of the 

 Mediterranean, or in Africa, as far south as the 

 Cape. The Black Kite is a regular summer 

 visitor to the forests of Central Europe, and the 

 example which was obtained on our shores doubt- 

 less lost its way in coming north in spring. Very 

 similar to the preceding species, in its summer 

 distribution in Europe, is the Scops Owl, which, 

 from time to time, pays us an uncertain visit in 

 the spring ; yet, so far as is known, neither of 

 these birds has ever bred in the British Islands 

 they are purely accidental wanderers from their 

 usual haunts. 



The Rock Thrush is another straggler here in 

 spring, far out of its usual habitat, its nearest 

 breeding-place being the Hartz Mountains, in 

 about the same latitude as London, though 500 

 miles to the east of that locality. Nearly all the 

 rare Warblers that pay us their irregular visits are 

 strangers of the spring. The only wonder is that 

 these species have not regularly extended their 

 migration to this country ; but the English 

 Channel appears to be a great barrier to many 

 migratory birds. This is one of the many pecu- 

 liarities of geographical distribution. In a great 

 many cases we find narrow seas forming the line 

 of demarcation between widely different faunas ; 

 and so far as the British Islands are concerned, 

 this seems to show that the birds which breed as 



