[page] 307

MR. DARWIN'S new book will revive an old controversy and furnish material for countless scientific essays. It is impossible to state in a bolder way than Mr. Darwin does the conclusions put forward in his "Descent of Man."

"Man," he says, confidently, "is descended from a hairy quadruped, furnished with a tail and pointed ears, probably arboreal in its habits, and an inhabitant of the Old World."

Elsewhere he traces this ancestor back to "the most ancient progenitors in the kingdom of the vertebrata, at which we are able to obtain an obscure glance, and who apparently consisted of a group of marine animals, resembling the larvae of existing Ascidians," and here he adds a pregnant note: -

"All vital functions tend to run their course in fixed and recurrent periods, and with tidal

animals the periods would probably be lunar; for such animals must have been left dry or

covered deep with water, -supplied with copious food or stinted, -during endless generations,

at regular lunar intervals. If then the vertebrata are descended from an animal allied to the existing tidal Ascidians, the mysterious fact that with the higher and now terrestrial

vertebrata, not to mention other classes, many normal and abnormal vital processes run their course according to lunar periods, is rendered intelligible. A recurrent period, if approximately of the right duration, when once gained, would not, as far as we can judge, be liable to be changed; consequently it might be thus transmitted during almost any number of generations. This conclusion, if it could be proved sound, would be curious; for we should then see that the period of gestation in each mammal, and the hatching of each bird's eggs, and many other vital processes, still betrayed the primordial birthplace of these animals."

These are some of what Mr. Darwin himself calls the "highly speculative views" that are to be found in one of the most remarkable books ever published.