Perhaps the most curious part of the history of the sea-horses relates to their care of the young. Fishes generally take little or no care of their offspring, and it is therefore the more surprising to encounter in these little beings a singular example of parental fidelity and attachment. Nor, as might be expected, is it the mother-fish who is charged with the task of attending the young. Contrary to the general rule, the male fish assumes the part of nurse, and well and faithfully does he appear to discharge his duties. At the root of the tail in the male sea-horse a curious little pouch is seen. In this pouch the eggs laid by the females--which want the pouch--are deposited, and are therein duly hatched. Nor does the parental duty end here; for after the young are hatched and swim about by themselves, they seek refuge in the pouch during the early or infantile period of their life whenever danger threatens them. This procedure forcibly reminds one of the analogous habits of the kangaroos and their young; but the occurrence is the more remarkable in the lower and presumably less intelligent fish. Some experiments made on the sea-horses seem to demonstrate the existence of a more than ordinary degree of attachment to the young. Thus when a parent-fish was taken out of the water, the young escaped from the pouch; but on the parent being held over the side of the boat, the young at once swam toward him, and re-entered the pouch without hesitation. Some authorities have not hesitated to express an opinion that the young are nourished within the pouch by some fluid or secretion of its lining membrane. But further observation is certainly necessary before this latter opinion can be relied upon. The pipe-fishes are very near neighbors of the sea-horses, and derive their name from the thin elongated shape of their bodies, together with the fact that the jaws are prolonged to form a long pipe-like snout, at the extremity of which the mouth opens. These fishes are very lively in all their movements, and dart through the water so quickly that in many cases the eye is unable to follow them. Like the sea-horses, the male pipe-fishes protect and tend their progeny, and exhibit an equal attachment to their young. These latter features are also well exemplified by the familiar sticklebacks of our ponds and streams. The latter fishes actually build nests for the reception and care of their eggs, the nests being made chiefly or solely by the males; while on the latter, during the process of hatching and in the upbringing of the young, devolves the chief care of protecting and looking after the welfare of the progeny. These instances of the care and duties which devolve on the males, instead of on the mother-parents, appear to reverse the more natural order which almost universally obtains in the case of both lower and higher animals.