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Cerebidæ, Tanagridæ, Cotingidæ, Conuridæ ; 1 is Antillean only—Todidæ ; while 1-Ampelidæ—is confined (in the western hemisphere) to North America, and almost to the Nearctic region. Of the 95 genera, no less than 31, or almost exactly one-third, are peculiar; while of the 203 resident species, 177 are peculiar, the other 26 being all inhabitants of South or Central America. Considering how closely the islands approach the continent in several places-Florida, Yucatan, and Venezuela—this amount of speciality in such locomotive creatures as birds, is probably unexampled in any other part of the globe. The most interesting of these peculiar genera are the following: 4 of Turdidæ, or thrushes-l confined to the large islands, 1 to the whole archipelago, while 2 are limited to the Lesser Antilles ; 2 genera of Tanagridæ, confined to the larger islands ; 2 of Trogonidæ, also confined to the larger islands ; 5 of hummingbirds, 3 confined to the Greater, 1 to the Lesser Antilles; 2 of cuckoos, one represented in all the large islands, the other in Jamaica only; 2 of owls, one peculiar to Jamaica, the other represented in St. Croix, St. Thomas, Portorico, and Cuba; and lastly, Todus, constituting a peculiar family, and having representative species in each of the larger islands is especially interesting because it belongs to a group of families which are wholly Neotropical—the Momotidæ, Galbulidæ, and Todidæ. The presence of this peculiar form, with 2 trogons 10 species of parrots, all but one peculiar; 16 peculiar humming-birds belonging to 8 genera; a genus of. Cotingidæ ; 10 peculiar tanagers belonging to 3 genera; 9 Cerebidæ of 3 genera ; together with species of such exclusively Netropical genera as Cæreba, Certhiola, Sycalis, Phonipara, Elainea, Pitangus, Campephilus, Chloronerpes, Nyctibius, Stenopsis, Lampornis, Calypte, Ara, Chrysotis, Zenaida, Leptoptila, and Geotrygon, sufficiently demonstrate the predominant affinities of this fauna; although there are many cases in which it is difficult to say, whether the ancestors of the peculiar genera or species may not have been derived from the Nearctic rather than from the Neotropical region.
The several islands differ considerably in their apparent pro
ductiveness, but this is, no doubt, partly due to our knowledge of Cuba and Jamaica being much more complete than of Hayti. The species of resident land-birds at present known are as follows:
Cuba 68 species of which 40 are peculiar to it.
41 Portorico 40
15 Lesser Antilles 45
If we count the peculiar genera of each island, and reckon as (1) when a genus is common to two islands only, the numbers are as follows :-Cuba 71, Hayti 33, Jamaica 81, Portorico 1, Lesser Antilles 37. These figures show us, that although Jamaica is one of the smaller and the most isolated of the four chief islands, it yet stands in the first rank, both for the number of its species and of its peculiar forms of birds,—and although this superiority may be in part due to its having been more investigated, it is probably not wholly so, since Cuba has also been well explored. This fact indicates, that the West Indian islands have undergone great changes, and that they were not peopled by immigration from surrounding countries while in the condition we now see them; for in that case the smaller and more remote islands would be very much poorer, while Cuba, which is not only the largest, but nearest to the mainland in two directions, would be immensely richer, just as it really is in migratory birds.
The number of birds common to the four larger islands is very small-probably not more than half a dozen ; between 20 and 30 are common to some two of the islands (counting the Lesser Antilles as one island) and a few to three; but the great mass of the species (at least 140) are confined each to some one of the five islands or groups we have indicated. This is an amount of isolation and speciality, probably not to be equalled elsewhere, and which must have required a remarkable series of physical changes to bring about. What those changes probably were, we shall be in a better position to consider when we have completed our survey of the various classes of land animals.