Page:Popular Science Monthly Volume 31.djvu/855

Rh and manners of fishes, and especially of the marine species, is but sporadic and fragmentary; opportunities for ohservation are rare on the sea-bottom, while, as for aquariums, the life there is so strained and unnatural that we learn for the most part little more from that source than one would learn of the intricacies of human existence by watching the interiors of prisons and of convents, But even among the few fish at all intimately known to us at present, there are several which deserve high commendation for their able and conscientious discharge of their paternal duties. Certain cat-fish, for example, and many other species, construct nests like good fathers, and guard the spawn deposited in them by their unnatural spouses. One siluroid bearing the suggestive classical name of Arius actually carries the eggs about with him in his own mouth, and there devotedly hatches them. There is a fish of the Sea of Galilee, locally supposed to be the very kind from whose mouth St. Peter took the miraculous denarius for the payment of the apostles' tribute, and this pious and well-principled creature (even his scientific name is Chromis sacra) holds his eggs in the same fashion, and hatches them out in his capacious pharynx. Among the pipe-fish and sea-horses, including the well-known hippocampus of the Mediterranean and the Westminster Aquarium, Nature has gone one step further in the direction of parental supervision. These fish have a regular pouch like the kangaroo, in which the excellent papa retains the young till they are of full age to shift for themselves.

Yet even here it is the fond father, not the gay and careless mother, who wheels about the family perambulator: only two known cases occur among fish where the mother takes any part at all in the hatching or education of her own young. One is a cat-fish from British Guiana, whose under surface becomes soft and spongy after the spawning-season. The mother, as soon as she has laid her eggs, presses them hard into this spongy integument by lying on top of them. There they stick, and she carries them about in the pits thus formed, much as the familiar Surinam toad carries about her hatching ova and tadpoles in the skin of her back. The other instance is that of a singular pipe-fish from the Indian Ocean, who forms a pouch for her young by allowing her ventral fins to coalesce with the soft skin of her under surface. These two examples of devoted maternity, however, scarcely suffice to absolve the mother-fish as a class from the general charge of heartless desertion brought against them by modern ichthyologists.

It is worth while, perhaps, to note in passing (since a theory of tittlebats is nothing if not exhaustive) that the eggs of stickleback are larger in proportion to the size of the full-grown individual than those of any other known fish. Why is this? Simply because the stickleback are good fathers, who take great care of their callow young. (I don't know what callow means, as applied to a fish, but I