This plate represents a group of fifteen-spined sticklebacks busily employed in making their nests. To the left is seen a curious piece of marine architecture, mentioned by Mr. Couch, the well-known ichthyologist. A pair of sticklebacks had made their nest "in the loose end of a rope, from which the separated strands hung out about a yard from the surface, over a depth of four or five fathoms, and to which the materials could only have been brought, of course, in the mouth of the fish, from the distance of about thirty feet. They were formed of the usual aggregation of the finer sorts of green and red sea-weed, but they were so matted together in the hollow formed by the untwisted strands of the rope that the mass constituted an oblong ball of nearly the size of the fist, in which had been deposited the scattered assemblage of spawn, and which was bound into shape with a thread of animal substance, which was passed through and through in various directions, while the rope itself formed an outside covering to the whole." The black Goby (_Gobius niger_) also prepares a nest for its eggs. This fish inhabits the slimy bottoms of the lagoons near Venice, and burrows galleries in the clayey soil, where it spends the greater part of the year, protected against storms and enemies. In spring it digs more superficial dwellings among the roots of the sea-grass, to which the spawn attaches itself. The architect watches over the entrance of the house, opposing sharp rows of teeth to every intruder. A similar care may be admired in the tiny Stickleback, which the celebrated ichthyologist, M. Coste, has often watched building its nest. After the fish has collected the materials, it covers them with sand, glues the walls with a mucous secretion, and prepares a suitable entrance. At a later period it becomes the bold and indefatigable defender of its eggs, repelling with tooth and prickles all other sticklebacks that approach the nest. If the enemy is too powerful, it has recourse to artifice, darts forth, seems actively engaged in the pursuit of an imaginary prey, and often succeeds in diverting the aggressor's attention from its nest. The River Bullhead is likewise said to evince the same parental affection for its ova, as a bird for its nest, returning quickly to the spot, and being unwilling to quit it when disturbed. It is believed, also, of the Lump-Sucker, that the male first keeps watch over the deposited ova, and guards them from every foe with the utmost courage. If driven from the spot by man, he does not go far, but is continually looking back, and in a short time returns. Thus we find among the inferior animals glimpses of a higher nature, which prove that all created beings form a continuous chain, linked together by one all-pervading and almighty Power. [Illustration: Internal Ear of Perch.] [Illustration: Osseous labyrinth of the Human Ear.