Purchase of this book includes free trial access to www.million-books.com where you can read more than a million books for free. This is an OCR edition with typos. Excerpt from book: affection, are necessary for the existence of certain species, although there are many other means by which a species may be enabled to subsist. Where parental care is lacking, we may be sure to find compensation for it in some other way. Among the Invertebrata, Fishes, and Reptiles, both parents are generally quite indifferent as to their progeny. An immense proportion of the latter therefore succumb before reaching maturity ; but the number of eggs laid is proportionate to the number of those lost, and the species fe preserved nevertheless. If every grain of roe spawned by the female fishes were fecundated and hatched, the sea would not be large enough to hold all the creatures resulting from them. The eggs of Reptiles need no maternal care, the embryo being developed by the heat of the sun ; and their young are from the outset able to help themselves, leading the same life as the adults. Among Birds, on the other hand, parental care is an absolute necessity. Equal and continual warmth is the first requirement for the development of the embryo and the preservation of the young ones. For this the mother almost always wants the assistance of the father, who provides her with necessaries, and sometimes relieves her of the brooding. Among Mammals, the young can never do without the mother at the tenderest age, but the father's aid is generally by no means indispensable. In some species, as the walrus,1 the elephant,1 the Bos ameri- canus8 and the bat,4 there seems to be a rather curious substitute for paternal protection, the females, together with their young ones, collecting in large herds or flocks apart from the males. In the case of the man-like apes there are some obvious facts which might account for the need of marital and paternal protection. One is the small number... --This text refers to an alternate Paperback edition.