The geographical distribution of animals, with a study of the relations ...

chap, v.] CLASSIFICATION. 93the most highly organised, but only one of the most specialisedforms of birds, and because their affinities are not with thePasseres, but rather with the cormorants and some otherof theaquatic groups. The Passeres therefore are placed first ; and theseries of families is begun by the thrushes, which are certainlythe most typical and generally well-organised form of birds.Instead of the Scansores and Fissirostres of the older authors, theorder Picarise, which includes them both, is adopted, but withsome reluctance; as the former are, generally speaking, well markedand strongly contrasted groups, although certain families havebeen shown to be intermediate.In the Picarise are included thegoat-suckers, swifts, and humming-birds, sometimes separatedas a distinct order, Macrochires. The parrots and the pigeonsform each a separate order. The old groups of Grallse andAnseres are preserved, as more convenient than breaking themup into widely separated parts ; for though the latter plan mayin some cases more strictly represent their affinities, its detailsare not yet established, nor is it much used by ornithologists.In accordance with these views the following is the series oforders and families of birds adopted in this work :Class—AVES.Orders.1 Passeres \ Including the great mass of the smaller birds—Crows,'\ Finches, Flycatchers, Creepers, Honeysuckers, &c, &c.2 Picari-e ""\( ^ncm^m g Woodpeckers, Cuckoos, Toucans, Kingfishers,Swifts, &c, &c.3. Psittaci . . . Parrots only.4. Columbee ... Pigeons and the Dodo.5. Gallinaa ... Grouse, Pheasants, Curassows, Mound-builders, &c.6. Opisthocomi The Hoazin only.7. Accipitres ... Eagles, Owls, and Vultures.8. Grallse ... Herons, Plovers, Eails, &c.9. Anseres ... Gulls, Ducks, Divers, &c10. Struthiones . . . Ostrich, Cassowary, Apteryx, &c.The Passeres consistof fifty families, which may be arrangedand grouped in series as follows. It must however be rememberedthat the first family in each series is not always thatwhich is most allied to the last family of the preceding series.All extensive natural groups consist of divergent or branchingalliances, which renders it impossible to arrange the whole inone continuous series.