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

xiiPREFACE.and conclusions would have nothing solid to rest on), these maybe omitted by the non-scientific reader, or merely noted as acertain number or proportion of peculiar generic types. ManyEnglish equivalents to family and generic names are, however,given; and, assisted by these, it is believed that any readercapable of understanding Lyell's "Principles," or Darwin's" Origin," will have no difficulty in following the main argumentsand appreciating the chief conclusions arrived at in thepresent work.To those who are more interested in facts than in theories,pie book will serve as a kind of dictionary of the geographyand affinities of animals. By means of the copious Index, thenative country, the systematic position, and the numericalextent of every important and well established genus of landanimalmay be at once discovered ;—information now scatteredthrough hundreds of volumes.In the difficult matters of synonymy, and the orthography ofgeneric names, I have been guided rather by general utilitythan by any fixed rules. When I have taken a whole familycroup from a modern author of repute, I have generally followedhis nomenclature throughout. In other cases, I use the nameswhich are to be found in a majority of modern authors, ratherthan follow the strict rule of priority in adopting some newlydiscovered appellation of early date. In orthography I haveadopted all such modern emendations as seem coming intogeneral use, and which do not lead to inconvenience ;but wherethe alteration is such as to completely change the pronunciationand appearance of a well-known word, I have not adopted it.I have also thought it best to preserve the initial letter of wellknownand old-establishedto the Indices of established works.names, for convenience of referenceAs an example I may referto Enicurus,—& name which has been in use nearly half a