CHAP. XIII.] 
THE GALAPAGOS ISLANDS. 
271 
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Fringillidje. 
Geospiza magnirostris 
„ strenua 
„ dubia 
,, fort is 
,, oebulosa ... 
„ fuliginosa... 
,, parvula 
,, dentirostris 
Cactornis scandens ... 
„ assimilis ... 
„ abingdoni 
,, pallida 
Carnarhynchus psittaculus 
,, crassirostris 
„ variegatus 
„ prosthemelas 
,, habeli ... 
A distinct genus, but allied to tho 
South American genus Guiraca. 
A genus allied to the last. 
A very peculiar genus allied to Neo- 
rhynchus of the west coast of 
Peru. 
Dolichonyx oryzivorus 
IcTERID^E. 
. . . .Ranges from Canada to Paraguay. 
Tyrannidae. 
Pyrocephalus nanus Allied to P. rvbineus of Ecuador. 
Myiarchus magnirostris Allied to West Indian species. 
Columbidjs. 
Zenaida galapagensia { A s P ecies of a S ' Amer!can 
Falconid^e. 
Buteo galapagensis ... A buzzard of peculiar coloration. 
Asio galapagensis ... 
Strix punctatissima ... 
Strigid^:. 
f Hardly distinct from the wide-spread 
\ A. brachyotus. 
Allied to tS.jiammea but quite distinct. 
We have here every gradation of difference from perfect 
identity with the continental species to genera so distinct that 
it is difficult to determine with what forms they are most nearly 
allied ; and it is interesting to note that this diversity bears a 
distinct relation to the probabilities of, and facilities for, migra- 
tion to the islands. The excessively abundant rice-bird, which 
breeds in Canada and swarms over the whole United States, 
migrating to the West Indies and South America, visiting the 
