WRITERS on popular entomology are hard driven nowaday to find titles for their works, or subjects that have not already been worn to shred s by previous authors. To be successful they must possess the same talent that enables a chef-de-cuisine to contrive an entrée from the same materials, so disguised by name and sauces as to lead his patrons to consider they are partaking of a new dish. The author of this nicely got up little book has evidently felt himself in such a position, but on the whole he has succeeded very well, the more so because there are fewer errors than ordinarily exist in popular entomological works. He takes as his standpoint the fact that very many insects are indisputably serviceable: some by ridding the world of putrid or unhealthy organic matters, both animal and vegetable; some by destroying other insects undoubtedly noxious. The result is that we get here a series of histories of individuals or groups detailed in popular language, often from personal observation, and for the most part well illustrated by woodcuts. The author evidently feels himself most at home in dealing with the Coleoptera, and, as we think, judiciously takes up the position that bark-beetles and wood-borers are scavengers, seeking to devour what is already morbid, and are not the cause of decay in the trees in which they are found. We fail to follow his account of the mechanism by which the click-beetles (p. 207) perform that acrobatic movement so familiar to our childhood in the shape of the “jumping frog”; to our mind the “mucro” that is the chief agent in this action is not “elastic.” Why are the Aphis-parasites known as Aphidius stated to be Chalcididœ (p. 168)? Why is a Syrphus larva figured (p. 160) as that of a “Golden-Eye,” or “Lace-Wing”? The introductory remarks and the concluding notes contain some very judicious reasoning on the aim and purpose of entomological studies, and we sincerely wish we could agree with the author (p. 236) that collectors, as opposed to students, are “now in a very small minority”; a vast improvement towards this end has undoubtedly taken place latterly, but the time for congratulation has not yet arrived. The Society under whose auspices this little book is published has done much towards popularising natural history in this country; this work may be classed amongst the best of the series, and no doubt in a second edition the author will revise it and rectify a few palpable errors.