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starved out and exterminated some of the smaller native rodents. Birds.—The birds of the Antilles, although very inferior in number and variety to those of the mainland, are yet sufficiently abundant and remarkable, to offer us good materials for elucidating the past history of the country, when aided by such indications as geology and physical geography can afford. The total number of land-birds which are permanent residents in the West India islands is, as nearly as can be ascertained from existing materials, 203. There are, in addition to this number, according to Prof. Baird, 88 migrants from North America, which either spend the winter in some of the islands or pass on to Central or South America. These migrants belong to 55 genera, and it is an interesting fact that so many as 40 of these genera have no resident representatives in the islands. This is important, as showing that this northern migration is probably a recent and superficial phenomenon, and has not produced any (or a very slight) permanent effect on the fauna. The migratory genera which have permanent residents, and almost always representative species, in the islands, are in most cases characteristic rather of the Neotropical than of the Nearctic fauna, as the following list will show; Turdus, Dendraco, Vireo, Polioptila, Agelarus, Icterus, Contopus, Myiarchus, Tyrannus, Antrostomus, Chordeiles, Coccyzus, Columba. By far the larger part of these birds visit Cuba only; 81 species being recorded as occurring in that island, while only 31 have been found in Jamacia, 12 in Porto Rico and St. Croix, and 2 in Tobago and Trinidad. Setting aside these migratory birds, as having no bearing on the origin of the true Antillean fauna, we will discuss the residents somewhat in detail. The resident land-birds (203 in number) belong to 95 genera and 26 families. Of these families 15 are cosmopolitan or nearly so–Turdidae, Sylviidae, Corvidae, Hirundinidae, Fringillidae, Picidae, Cuculidae, Caprimulgidae, Cypselidae, Trogonidae, Psittacidae, Columbidae, Tetraonidae, Falconidae, and Strigidae; 5 are American only—Vireonidae, Mniotiltidae, Icteridae, Tyrannidae, Trochilidae ; 4 are Netropical only or almost exclusively— Coerebidae, Tanagridae, Cotingidae, Conuridae; 1 is Antillean only–Todidae; while 1–Ampelidae—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 Turdidae, or thrushes—l confined to the large islands, 1 to the whole archipelago, while 2 are limited to the Lesser Antilles; 2 genera of Tanagridae, confined to the larger islands; 2 of Trogonidae, 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 Momotidae, Galbulidae, and Todidae. 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 Cotingidae; 10 peculiar tanagers belonging to 3 genera; 9 Coerebidae of 3 genera; together with species of such exclusively Netropical genera as Coereba, Certhiola, Sycalis, Phonipara, Elainea, Pitangus, Campephilus, Chloromerpes, 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 proWOL. II. F

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:—

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If we count the peculiar genera of each island, and reckon as () when a genus is common to two islands only, the numbers are as follows:—Cuba 74, Hayti 3}, Jamaica 84, Portorico 1, Lesser Antilles 3}. 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.

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