188 OBIGIN OF LIFE IN AMERICA 



Dr. Wallace * makes the statement that the few species of 

 birds which are resident in Bermuda and breed on the island 

 are so constantly crossed by individual migrants of the same 

 species from the mainland that none of the former have 

 acquired any .special peculiarity constituting even a distinct 

 variety. It is perfectly true that the resident land birds 

 are very few in number, but the opinions, of most recent autho- 

 rities differ very considerably from those enunciated by Dr. 

 Wallace. 



Only ten species of land birds are resident on the island, 

 and three of these have been introduced by man. The indi- 

 genous fauna includes, therefore, seven "kinds of birds, 

 namely, the ground dove, the Florida gallinule, the crow, the 

 white-eyed Vireo, the blue bird, the cat bird and the cardinal. 



Of these the Bermuda ground dove (Columbigallina bermu- 

 diana) is described as a species very distinct from the 

 American C. passerina. The Florida gallinule (Gallinula 

 galeata) does not seem to differ from the continental form. 

 The crow of Bermuda is probably separable from the American 

 crow, but has not been sufficiently studied. The white-eyed 

 Vireo (Vireo bermudianus) is described by Messrs. Bangs 

 and Bradlee as very different in all its ways from its shy, 

 retiring, continental relative, V. noveboracensis.f The blue 

 bird is not usually recognised as distinct from the continental 

 form, but Dr. Sharpe of the British Museum held that its 

 characters were certainly striking enough to deserve specific 

 recognition, and he described it as Sialis bermudianus. Now I 

 may mention that the blue bird belongs to one of those genera 

 which seem to have retained their generic characters for very 

 long ages past, probably throughout several geological periods. 

 We know nothing of its past history from palaeontological evi- 

 dence, but its present geographical distribution, and that of- 

 its nearest relative, are so peculiar as to suggest their being of 

 great antiquity. Sialis, with its three closely-allied American 

 species, has its nearest relative (Grandala) in the Himalayan 

 Mountains. I only mention this fact so as to show that the 

 apparent specific identity of the Bermudan and the continental 



* Wallace, A. E., " Island Life," p. 269. 



t Bangs, 0., and T. S. Bradlee, " Birds of Bermuda," pp. 249257. 



