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Recent Literature. 



TAuk 

 |_Oct. 



that he did not describe these two specimens which "clearly show" what 

 large series of specimens of allied species have previously failed to prove. 



From Curasao Mr. Hartert records twenty-eight species of land-birds 

 and eleven of water-birds, being all that have been identified with cer- 

 tainty from this island. 



The relationships of the Euethia bicolor group are here discussed at 

 length, and four forms are recognized, — bicolor, from the Bahamas and 

 Lesser Antilles; marchi from Jamaica, San Domingo and Barbados [ ?] ; 

 sharpei from Aruba, Curacao, and Bonaire, and ommisa from Colombia, 

 Venezuela, and Tobago. 



Bonaire, the third island to be visited by Mr. Hartert, is described as 

 the "most oceanic of the three" and "generally more wooded than the 

 other three." Twenty-three species of land-birds and fifteen species of 

 water-birds were found on this island. The occurrence here of the West 

 Indian Margarofs fuscatus and Ammod ramus savannarum is among 

 the most interesting of Mr. Hartert's discoveries. 



He concludes by calling attention to the "striking affinities between 

 the avifauna of these islands and that of the islands of St. Thomas and 

 St. Croix (Virgin Islands), but no similarity to that of the Windward 

 Islands." These facts, Mr. Hartert thinks, "seem to point to the theory 

 that the Virgin Islands and the Islands of Bonaire and Curacao were 

 formerly connected in some way, or that they are of the same geological 

 age, and not of the same age as the Windward Islands." He adds : "Per- 

 haps there was once a line of islands (similar to that of the Lesser 

 Antilles) reaching from St. Thomas through 'Los Aves,' or the Bird 

 Island, by way of Blanca, Orchilla, Grand Cay, Los Roques, and the 

 second group called 'Los Aves,' to Bonaire and Curacao." It seems to 

 us, however, that the facts of the case are too unimportant to justify Mr. 

 Hartert's reckless island-building in the great depths of the Caribbean 

 Basin. The islands off the Venezuelan coast are oceanic and their avi- 

 fauna like that of most oceanic islands is in part due to purely fortuitous 

 circumstances. Accidental visitors which would stand little chance of 

 surviving in more thickly populated regions here find an isolation favorable 

 to their existence. Their presence is thus not necessarily to be accounted 

 for by actual geographical connection with the habitat of their nearest 

 allies. Again similar causes may produce similar results. The Bahaman 

 Geothlypis finds its nearest relative in the Lower Californian species, hut 

 there is no reason to doubt that it was derived from the Florida form from 

 which it has changed in the direction of the western species. Most of the 

 West Indian species occurring on Aruba, Bonaire, and Curacao are found 

 as slightly differentiated races in the Windward Islands, and it is quite 

 possible that some of them have been derived from this source and sub- 

 sequently have become changed to forms more closely resembling those 

 found in the Virgin Islands. 



Furthermore, as oceanic islands of apparently great age (Mr. Hartert 

 suggests that they may be older than the Windward Islands), it is not 



