A PUZZLING BIRD. 



161 



from its nearness to the mainland and the height of its 

 mountains, contains a few resident species not found in 

 the other Leeward Islands,* we may (with one or two 

 exceptions to be noticed later) say the same of all the 

 purely resident land-birds found in the islands of this out- 

 lying group. That is to say, they are all species which 

 have been derived from the mainland or from the wind- 

 ward group of the West Indian islands ; but from their 

 prolonged isolation in these outlying islands, they 

 have become modified into sub-species, climatic races, 

 or geographical forms, whichever you prefer to caU 

 them. 



Favourably situated as the islands are, in the matter of 

 intercepting stragglers driven out to sea by the Trade- 

 winds, they have acted, in some degree, as a net, 

 which has " mopped up," from time to time, influxes of 

 unwilling emigrants from the Antilles and the mainland . 



Why the Blanquilla grass-quit should have assumed 

 an even darker colouration than the Venezuelan bird, 

 while the Cura9ao grass-quit (E. sharpei) has become 

 modified in an opposite direction, until its imder-parfcs 

 have assumed almost a light alate-colour, is a difficult 

 matter to explain, seeing that the conditions under which 

 both species live are apparently quite identical. 



The ruby-and-topaz humming-bird, whose acquaint- 

 ance we first made on the island of Blanquilla, almost 

 immediately we had landed, was rather a puzzle to us. 

 On our first visit to the island in the month of April, this 

 delightful little bird was everywhere evident, and charmed 

 us with its jewel- like scintillations. It frequented the 

 thickest of the cactus patches ; darting in and out between 

 their tall columnar stems, hovering over a flower here 

 or a cactus fruit there ; and leading us onto many a prickly 

 chase. We shot and preserved a series of eight, and if so 

 disposed could have secured more. In February of the 

 following year, although we covered far more ground than 



* By " Leeward Islands " I mean the chain strung out along the 

 Venezuelan Coast. 



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