evolution; he is more concerned with the appearance of the living form than with its structure; but he is, nevertheless, not seldom, a master of his craft. The value of his observations was appraised and canonized by Darwin; but that it should be less superficial, that it should be more introspective, have a wider meaning, and a more philosophical clue, is unquestionable, and a book like this supplies the one thing needful. Zoology can neither be divorced from the fields nor from the laboratory—it is part and parcel of our own history; in an evolutionary sense "our birth is but a sleep and a forgetting"; and even the Echinoderma, when thus described, and the inseparable technicalities absorbed by the ready mother wit of both student and peasant, will increase our knowledge of what they are, and our perception of what we are.
There is a most excellent bibliography attached to each branch of the subject; and the book is far more than a zoological ledger posted up to date.
Most naturalists are familiar with Darwin's theory of "Sexual Selection," a theory which perhaps met with less general acceptance than any other put forward by our great biological philosopher, being even vigorously opposed by Mr. Wallace, his fellow-enunciator of the doctrine of "Natural Selection." Mr. Cunningham not only offers another hypothesis, but altogether starts from a Lamarckian standpoint, and is quite outside the views of either Darwin or Wallace on the subject, frankly stating that his object is to point out "how remarkably the multitudinous facts all agree with the hypothesis that secondary sexual characters are due to the inheritance of acquired characters." This course leads the author to some most startling speculations. His conclusion being "that the direct effects of regularly recurrent stimulations are sooner or later developed by heredity, but only in association with the physiological conditions under which they were originally produced," we meet with the following suggestions as to the origin of the beard in males, which "it is probable
