CHAP. II.] THE ELEMENTARY FACTS OF DISTRIBUTION. 15 



species or as to its geographical limits being really known. In 

 Europe we have a distinct species of ibex (Ga^ra Pyrenaica) 

 confined to the Pyrenean mountains, while the true marmot 

 is restricted to the Alpine range. More remarkable is the 

 Pyrenean water-mole {Mygale Pyrenaica), a curious small in- 

 sectivorous animal found only in a few places in the northern 

 valleys of the Pyrenees. In islands there are many cases of 

 undoubted restriction of species to a small area, but these 

 involve a different question from the range of species on 

 continents where there is no apparent obstacle to their wider 

 extension. 



Specific range of Birds. — Among birds we find instances of 

 much wider range of species, which is only what might be 

 expected considering their powers of flight ; but, what is very 

 curious, we also find more striking (though perhaps not more 

 frequent) examples of extreme limitation of range among birds 

 than among mammals. Of the former phenomenon perhaps 

 the most remarkable case is that afforded by the osprey or 

 fishing-hawk, which ranges over the greater portion of all the 

 continents, as far as Brazil, South Africa, the Malay Islands, and 

 Tasmania. The barn-owl (Strix fiammea) has nearly as wide a 

 range, but in this case there is more diversity of opinion as to 

 the specific difference of many of the forms inhabiting remote 

 countries, some of Vv/hich seem undoubtedly to be distinct. 

 Among passerine birds the raven has probably the widest range, 

 extending from the arctic regions to Texas and New Mexico in 

 America, and to North India and Lake Baikal in Asia; while 

 the little northern willow-wren {Phylloscopus horealis) ranges 

 from Norway across Asia to Alaska, and southward to Ceylon, 

 China, Borneo, and Timor. 



Of very restricted continental ranges the best examples in 

 Europe are, the little blue magpie (Cyanopica cooki) confined to 

 the central portions of the Spanish peninsula ; and the Italian 

 sparrow found only in Italy and Corsica. In Asia, Palestine 

 affords some examples of birds of very restricted range — a 

 beautiful sun-bird [Nectarinea osea) a peculiar starling {Amy- 

 dries Tristramii) and some others, being almost or quite con- 

 fined to the warmer portions of the valley of the Jordan. In 



