National Geographic : 1898 May
244 THE ORIGIN OF WEST INDIA BIRD-LIFE are to the mainland. One family (Todidre) and 38 genera are peculiar. The latter are represented by 96 species, leaving 209 species belonging to genera of North, South, or Central America but for the most part they have no near mainland allies, and in comparatively few cases can we point with probable exactness to their continental ancestors. In other words, taken as a whole, the endemic birds of the West Indies are widely differentiated from their parent stock. Considering now the faunal relationships of the islands inter se, we find at once that they can be divided into the two groups of physical geographers-the Greater and the Lesser Antilles. With the former belong the Virgin islands and St Croix; with the latter Sombrero, Anguilla, and the other islands east of the Anegada channel and southward to and including Grenada. While some genera (e. g., Myiadestes and Quiscalus) are repre sented by more or less closely allied species in both the Greater and Lesser Antilles, and while certain species characteristic of each group (e. g., Margarops,Bellona, and Mimocichla spp.) intrude to some extent into the other, their avifaune are quite unlike. The more distinct West Indian species are found only in the Greater Antilles. Thus the Todidse are represented in each of the larger islands of the Greater Antilles, but are known in the Lesser Antilles. In short, the relationships of the avifauna of these two groups are quite in accord with Mr Agassiz's statement that " the Windward islands were probably raised long after the range of the greater West Indian islands existed * * *" Some 108 resident land birds have been found in the Lesser Antilles. Sixteen of these are South American, of which thir teen occur in the Lesser but not in the Greater Antilles, and fourteen are West Indian species, which occur in both the Greater and the Lesser Antilles. Eight genera are peculiar, whereas in the Greater Antilles twenty-four genera are peculiar. These eight genera contain seventeen species upon whose origin we can only speculate. Subtracting them from the eighty-one endemic land birds, we have left sixty-four species, which may be grouped according to their apparent relationships as follows : Tropical.............. .. .......... 22 South American ........... .............. 19 W estIndian ............. ....... . ... . 23 The South American element here shown to be present in the Lesser Antilles at once suggests the possibility of a former land * Three Cruises of the Blake, ii, p. 113, foot-note.