A Book of Natural History | Page 7

eggs may drop under the stones or float away, and so escape the vital touch of the fertilizing principle. There are so many that numbers may be lost and yet enough remain to continue the family. Not so with the frog family. No egg may be lost. So we find that the eggs of the frog are not dropped singly, like so many shot, but are bound together by a colorless, transparent, jelly-like substance, much like that found in the morning-glory seed, and which like that supplies nourishment to the young life, for the tadpole feeds upon it until he is able to seek other food. Moreover, instinct has taught the frog the need of extreme caution in the act of fertilization. Every egg must be fertilized. As the time draws near for the dropping of the few eggs into the water, the male frog so places himself that the moment the eggs are being laid, he pours over them, one by one, as they fall into the water, the fertilizing fluid.
And thus the mystery of life is again repeated. The union of the living, microscopic bodies of the fertilizing principle with the new laid egg is followed by the growth of the two elements into a living creature, able to eat, to breathe, to see, to feel. In some unknown way the atom of fertilizing principle seems to have contained the whole life of the father-frog, for it can give to his sons and daughters any of his peculiarities, either of color, form, motion, or disposition; and the tiny egg seems to have contained the whole life of the mother-frog, and can give to her sons and daughters any of her peculiarities; though, as is true of all inheritance, the tadpoles, as the young frogs are called, share the natures of both parents, inheriting some peculiarities from the father and others from the mother.
[Illustration: A FROG.]
But, like other life, although the frogs may vary a good deal within frog limits, none of them can escape their own limits and enter into those of any other life. Once a frog, always a frog; and no frog-egg may hope to develop into a turtle, or a bird, or anything but a frog. The life in the fertilizing principle of the frog is sacred to frog eggs, and is lifeless in contact with any other.
Our common frogs, like many of the fishes, do not trouble themselves about the fate of their eggs after they are carefully laid in a safe place. They trust Mother Nature to see the little tadpoles safely through the perils of childhood, to help them change their dresses and get rid of their tails, and cut, not their teeth, but their arms and legs.
In Venezuela, however, there dwells a frog with well developed maternal instinct. The mothers have pockets on their backs, not for their own convenience, but as cradles for their babies. The fathers put the fertilized eggs into the pockets of the mothers; and there they remain, well guarded, until the young are able to care for themselves.
[Illustration: TADPOLES.]

THE MAN-LIKE APES
(FROM EVIDENCE AS TO MAN'S PLACE IN NATURE.)
BY PROFESSOR T.?H. HUXLEY.
[Illustration: HEAD OF GORILLA.]
Sound knowledge respecting the habits and mode of life of the man-like Apes has been even more difficult of attainment than correct information regarding their structure.
Once in a generation, a Wallace may be found physically, mentally, and morally qualified to wander unscathed through the tropical wilds of America and of Asia, to form magnificent collections as he wanders, and withal to think out sagaciously the conclusions suggested by his collections; but, to the ordinary explorer or collector, the dense forests of equatorial Asia and Africa, which constitute the favorite habitation of the Orang, the Chimpanzee, and the Gorilla, present difficulties of no ordinary magnitude; and the man who risks his life by even a short visit to the malarious shores of those regions may well be excused if he shrinks from facing the dangers of the interior; if he contents himself with stimulating the industry of the better-seasoned natives, and collecting and collating the more or less mythical reports and traditions with which they are too ready to supply him.
In such a manner most of the earlier accounts of the habits of the man-like Apes originated; and even now a good deal of what passes current must be admitted to have no very safe foundation. The best information we possess is that based almost wholly on direct European testimony respecting the Gibbons; the next best evidence relates to the Orangs; while our knowledge of the habits of the Chimpanzee and the Gorilla stands much in need of support and enlargement by additional testimony from instructed European eye-witnesses.
It will therefore be convenient in endeavoring to form a notion of what we are justified in