GEOGRAPHICAL DISTRIBUTION OF ANIMALS
BY HANS GADOW, M.A., Ph.D., F.R.S. Strickland Curator and Lecturer on Zoology in the University of Cambridge.
THE first general ideas about geographical distribution may be found in some of the brilliant speculations contained in Buffon Histoire Naturelle. The first special treatise on the subject was however written in 1777 by E. A. W. Zimmermann, Professor of Natural Science at Brunswick, whose large volume, Specimen Zoologiae Geographicae Quadrupedum..., deals in a statistical way with the mammals; important features of the large accompanying map of the world are the ranges of mountains and the names of hundreds of genera indicating their geographical range. In a second work he laid special stress on domesticated animals with reference to the spreading of the various races of Mankind.
In the following year appeared the Philosophia Entomologica by J. C. Fabricius, who was the first to divide the world into eight regions. In 1803 G. R. Treviranus1 devoted a long chapter of his great work on Biologie to a philosophical and coherent treatment of the distribution of the whole animal kingdom. Remarkable progress was made in 1810 by F. Tiedemann2 of Heidelberg. Few, if any, of the many subsequent Ornithologists seem to have appreciated, or known of, the ingenious way in which Tiedemann marshalled his statistics in order to arrive at general conclusions. There are, for instance, long lists of birds arranged in accordance with their occurrence in one or more continents: by correlating the distribution of the birds with their food he concludes "that the countries of the East Indian flora have no vegetable feeders in common with America," and "that it is probably due to the great peculiarity of the African flora that Africa has few phytophagous kinds in common with other countries, whilst zoophagous birds have a far more independent, often cosmopolitan, distribution." There are also remarkable chapters on the influence of environment, distribution, and migration, upon the structure of the Birds! In short,____________________