This volume is a proof of the steady though rapid progress which our great Natural History Collection is making, and is a token as well that under the present keeper of the Zoological Department, the stores of specimens will be made fully available for scientific reference. To the working zoologist there can be no more acceptable gift than such carefully compiled catalogues, and by the publication of such the collection itself not only indirectly but even directly benefits, for an interest is awakened in the objects described, and thereby the stream of donations begins to flow. The first edition of this Catalogue, published in 1858, contained the description of some 283 species, and the collection consisted of some 1691 specimens. The present edition contains the description of 800 species, of which the British Museum possesses 522, represented by some 4692 specimens. The first edition, by Dr. Günther, without doubt gave a great impulse to the study of the tailless Batrachians, and as a result it is now out of date. For the present edition Dr. Günther has been fortunate in securing the services of Mr. Boulenger, the assistant naturalist in the Royal Museum of Belgium, and exceedingly well has the latter accomplished his task. The classification adopted is based on that of Mr. E. D. Cope, somewhat modified, and biologists in general will be pleased to know that this classification seems to harmonise not only with the natural affinities of the genera, but with all that is known of the geographical distribution, development, and physiology of the group. The only serious objection urged against it is the supposed difficulty of ascertaining on the recent specimens the osteological characters, without sacrificing one or more specimens; but, as Mr. Boulenger asserts, it requires only a moderate skill and two or three clean incisions to reveal all the required secrets of the structure of the vertebræ.