May it not be that the parents, finding all efforts to restore their young to freedom ineffectual, sought this method of saving them from a life to which death must assuredly be preferable? Instances of like character might be adduced by the hundred, but enough has been written to show that, in the case of _Formica flava_, an unwillingness to allow the humblest of the colony to be taken into bondage was the motive which prompted the sacrifice. NEST-BUILDING FISHES. Not alone in color do fishes resemble birds. In the home-life and love of offspring a close resemblance obtains. Many are nest-builders, erecting structures quite as complicated as those of some birds, and hardly less elaborate in design and finish. Floating along some woodland stream, or strolling along its grass-fringed margin, we have watched the domestic life of the Sun-fish, the _Eupomotis vulgaris_ of writers, that mottled, bespangled beauty that seems always on hand to be caught by the angler in default of more noble game. Where delicate grasses grow, and floating lily-pads cast their shadows, there among the winding stems the Sun-fish builds its home. Moving in pairs in and out among the lilies near the shore, as if jointly selecting a site for a nursery, they may be seen. The spot is generally a gravelly one, and, once determined upon, no time is lost in pushing the work to a speedy conclusion. For several inches around the space is cleared of stems or roots, and these are carefully carried away. The smaller roots are swept aside by well-directed blows of their tails, or by mimic whirlpools which the fishes, standing over the nest, create by their fins. The stones are next taken up, the smaller ones in their mouths, the larger being pushed out bodily, or fanned away by the sweeping process, until an oval depression, with a sandy bottom, finally appears. About the sides the stems of aquatic verdure, which seem to have been purposely left, may be seen standing, and these now naturally fall over, oftentimes constituting the nest a perfect bower, with walls bedecked with buds, while the roof is a mat of white lilies floating upon the surface. Here the eggs are deposited, the male and female alternately watching them. [Illustration: NEST OF COMMON SUN-FISH. Male and Female Defending It from Attack of Cat-fish.]