24 ISLAND LIFE part i 



that of the bhie magpies, forming the genus Cyanopica. 

 One species ( C. cooki) is confined (as ah'eady stated) to the 

 wooded and mountainous districts of Spain and Portugal, 

 while the only other species of the genus {C. cyayius) is 

 found far away in North-eastern Asia and Japan, so that 

 the two species are separated by about 5,000 miles of 

 continuous land. Another case is that of the curious little 

 water-moles forming the genus My gale, one species M. 

 muscovitica, being found only on the banks of the Volga 

 and Don in South-eastern Russia, while the other, M. 

 injrenaica, is confined to streams on the northern side of 

 the Pyrenees. In tropical America there are four different 

 kinds of bell-birds belonging to the genus Chasmorhynchus, 

 each of which appears to inhabit a restricted area com- 

 pletely separated from the others. The most northerly 

 is C. tricarunculahts of Costa Rica and Veragua, a brown 

 bird Avith a white head and three long caruncles growing 

 ujjwards at the base of the beak. Next comes C. variegatus, 

 in Venezuela, a white bird with a brown head and nu- 

 merous caruncles on the throat, perhaj^s conterminous with 

 the last ; in Guiana, extending to near the mouth of the 

 Rio Negro, Ave have C. nivcus, the bell-bird described by 

 Waterton, Avhich is pure wdiite, with a single long fleshy 

 caruncle at the base of the beak ; the last species, C. 

 nndicoUis, inhabits South-east Brazil, and is also white, 

 but "with black stripes over the eyes, and with a naked 

 throat. These birds are about the size of thrushes, and 

 are all remarkable for their loud, rinoino- notes, like a bell 

 or a blow on an anvil, as Avell as for their peculiar colours. 

 They are therefore known to the native Indians wherever 

 they exist, and we may be the more sure that they do not 

 spread over the intervening areas where they have never 

 been found, and Avhere the natiA^es knoAV nothing of 

 them. 



A good example of isolated species of a group nearer 

 home, is afforded by the snoAv-partridges of the genus 

 Tetraogallus. One species inhabits the Caucasus range 

 and noAvhere else, keeping to the higher slopes from 6,000 

 to 11,000 feet above the sea, and accompanying the ibex in 

 its Avanderings, as both feed on the same plants. Another 



