present, and hence Dr. Sharp does not consider it too much to anticipate that 30,000 or even 40,000 forms may yet be acquired. We quite agree with him, however, in the opinion that "the species of Rhopalocera seem to be peculiarly liable to dimorphic, to seasonal, and to local variation; so that it is possible that ultimately the number of true species—that is, forms that do not breed together actually or by means of intermediates, morphological or chronological—may have to be considerably reduced."
In the almost congested entomological literature of the present day, this work will long maintain a distinctly acknowledged individuality.
This is a polemic, but a valuable one. It is almost precisely on the lines and argument of Prof. Mcintosh's 'Resources of the Sea,' which was noticed recently in these pages (ante, p. 188), being a protest against the State's interference with man's livelihood by means of the fishing industry. Of course this is a very wide question. Is our supply of marine fishes seriously jeopardized by the action of the free use of the trawl and net? Many hold that it is, as, for instance, Prof. Herdman, who is treated in this reprinted lecture very frankly by Mr. Jackson, who, on the contrary, holds that the enormous fecundity of most marine animals is an all-sufficient protection against the destructive influence of man. We have described this publication as a polemic, but a valuable one. Its very strenuous advocacy makes it the first; its many excellent recorded facts and observations redeem it, and constitute it a welcome addition to the literature of the subject. Perhaps, however, the author was more concerned with the controversial element; still the natural history reader will probably forget the sorrows of the fishermen, and revel in the anecdotal details of the life-histories of his prey.
