We are, however, somewhat puzzled by the Preface as to the authorship of this volume. Thus we read:—"Only one chapter in the book (Chapter XIV.) remains practically unaltered from the first edition, so that while the credit for the general plan of the work belongs to Mr. H.S. Wells, no responsibility attaches to him for any part of the present work." Who then is the writer who has "almost completely rewritten the book"? for we are told Mrs. Davies has supplied the diagrams to this volume of "the University Tutorial Series."
The "type-system" is employed throughout, pages 1–134 being devoted to a very thorough exposition of the Rabbit. We cannot devote a space in these pages sufficient to adequately notice the anatomical and physiological treatment of the subject, but those of our readers, who do not pay much attention to those important aspects of zoology, will still find many interesting conclusions in the life-history of the animal. Many points, often overlooked, are brought out very clearly and in plain language.
"Thus the Rabbit is dependent on the plant kingdom for the maintenance of its life. So, too, are all animals, directly or indirectly; for, though one animal may feed on another, and that in turn on another, this process cannot be carried on indefinitely: sooner or later we must come down to an animal which is a plant-feeder. In the long run all animals are dependent on plants for both the material and the energy of their bodies."
Again, in rightly estimating a subject so often misunderstood as "variation," it is well to bear in mind that "it is probable that out of the enormous numbers of Rabbits that live or have lived no two have ever been exactly alike." Perhaps, however, a strong and excellent theory is made too much a fact, when we are told that the upturned white tail of the Rabbit " serves as a 'recognition mark' to guide the young when during feeding an alarm is given, and a bolt is made for the burrows." This is a probability; and even Wallace does not confine its efficacious protection to the young alone, bat to those "more remote from home," as well as to the young and feeble.
Part II. is devoted to the "Lower Vertebrata," of which the Frog, Dogfish, and Lancelet are taken as types; Part III. treats of the "Development of Vertebrata"; and Part IV. deals with the "Invertebrata," the Slipper-Animalcule (Paramecium aurelia),
