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. Plate XVII. [Illustration] A SCENE IN CUBA, WITH CHARACTERISTIC ANIMALS. {67}In the preceding enumeration the Bahamas have been included with Cuba, as regards the birds they have in common; but they possess some half dozen species not found elsewhere, and even one central American genus of humming-birds (_Doricha_) not found in any other part of the Antilles. We have thus given Cuba rather more peculiar species than it really possesses, so that the proportionate richness of Jamaica is rather greater than shown by our figures. The destruction of the forests and the increase of population, with, perhaps, the use of firearms, seem to have led to the extermination of some species of birds in the smaller islands. Professor Newton has called attention to the work of M. Ledru, who, in 1796, described the birds of St. Thomas. He mentions a parrot and a parroquet in the island, the latter only being now known, and very scarce; also a green pigeon and a tody, both now unknown. No less than six species of parrots are said to have been formerly found in Guadeloupe and Martinique, which are now extinct.