A Check-List of the Slugs (Classic Reprint)

Excerpt from A Check-List of the Slugs L. Rgzzamz/zatz'zms, Morelet, &c., have for years been completely misunderstood. Another difficulty relates to the limit Of species. In England we find comparatively few species, and these for the most part very distinct from one another, so that we are hardly prepared for the numerous closely allied forms of Southern Europe and elsewhere. [jmax maximus and L. żames, for instance, are subgenerically distinct; and English authors having in mind suich distinctions as they present, have at various times refused to recognise species or subspecies differing in less degree. Thus Anon lzortezzsly and A. Fare/alas, T erlaeella lzalz'olz'zlea and T. Sezzz'zelzem,' and other valid species,'have been long confounded. When we examine the maxi/mes group of Liz/mac, the gagates group Of Amalia, the law's group of agrloll/i/ax, &c., the sharp distinctions between species seem to be altogether lost. In Central Europe the subspecies or species allied to Limax maxi/1m; are numerous and polymorphic, so that, despairing of finding good lines of separation, authors have sometimes proposed to unite them under a single name. Yet to thus confound maxz'mzzs, ez'nereo-myer, and geogmp/zz'ezzs, &c., tends rather to obscure facts of great interest, and in the present list all such forms are given the rank Of subspecies, which seems best to express their true standing. This gradation of forms, though so annoying to the pure systematist, is to the evolutionist full of interest, and the more carefully the units (whether species, subspecies, or varieties) are studied, the greater is the light thrown on the making Of species. The slugs are by no means exceptional in furnishing such evidence Of evolution, and it is very instructive to notice the way in which the difficulties of classification have been met in different groups of organisms. The student may be referred to the writings of Allen and Merriam on North American Rodents, of W. H. Edwards on Aggy/2min of C. B. Adams on Jamaican Land Shells, Of Bebb and Buchanan White on willows, of Baker on roses, &c., for similar instances. About the Publisher Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com This book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully; any imperfections that remain are intentionally left to preserve the state of such historical works.