We give a few of the large number of testimonials relating to the character of this work.
Not only does your book fully justify its title for its clearness and the concise presentation of a difficult subject, but it is emphatically a guide to the study of insects injurious to vegetation, owing to the constant reference it contains to topics pertaining to economic entomology. I will say more: I hold that your work ought, in connection with Harris's "Treatise on Insects Injurious to Vegetation," to which it is, as it were, the Key, to be introduced in all our Agricultural Colleges, as the best text-book of that kind now extant.—Extract from letter of Prof. L. Agassiz.
I have received Part ten of your Guide To the Study of Insects, which brings the whole work so successfully to its completion. After all the good things that have been said of it at home and abroad, any commendation of mine would be quite superfluous. I will, however, express my obligation for both the pleasure and instruction I have received in reading it.—Extract from letter of Prof. T. Wyman.
The first two parts are, we do not hesitate to affirm, the best things of the kind that our language possesses. We have seldom fallen on so thoroughly good a scientific treatise as the one whose features we have briefly sketched, and we can only conclude our notice of it by advising all our natural history readers to make its acquaintance. There is no work we should prefer to it as a book for the student, for it is a treatise which displays an absolute avoidance of mere compilation, and it is pervaded by such a tone of earnestness, and contains so many original observations, that the reader is inducted by it out of the usual book-land of idealism into the substantial region of actuality and fact.—Scientific Opinion, London.
Too often do we meet with a manual in which there is little more than a description of the external characters which nobody is satisfied with, because it is not full enough for the mere collector, and for the general reader is too dry. Packard's work has succeeded throughout in satisfying.
THE MAMMOTH CAVE AND ITS INHABITANTS,
Or Descriptions of the Fishes, Insects and Crustaceans
found in the Cave; with figures of the various species, and an account of allied forms, comprising notes upon their Structure, Development and Habits; with remarks upon subterranean life in general.