charge. But this is a public and official attitude. In private, we can despise the distinctions established by others, but keep a corner of favouritism for our own.[24] I remember once showing a bottle containing Polypes to a philosopher, who beheld them with great calmness. They appeared to him as insignificant as so many stems of duckweed; and lest you should be equally indifferent, I will at once inform you that these creatures will interest you as much as any that can be found in ponds, if you take the trouble of studying them. They can be cut into many pieces, and each piece will grow into a perfect Polype; they may be pricked, or irritated, and the irritated spot will bud a young Polype, as a plant buds; they may be turned inside out, and their skin will become a stomach, their stomach a skin. They have acute sensibility to light (towards which they always move), and to the slightest touch; yet not a trace of a nervous tissue is to be found in them. They have powers of motion, and locomotion, yet their muscles are simply a network of large contractile cells. If the water in which they are kept be not very pure, they will be found infested with parasites; and quite recently I have noticed an animal, or vegetal, parasite--I know not which--forming an elegant sort of fringe to the tentacles: clusters of skittle-shaped bodies, too entirely transparent for any structure whatever to be made out, in active agitation, like leaves fluttering on a twig. Some day or other we may have occasion to treat of the Polypes in detail, and to narrate the amusing story of their discovery; but what has already been said will serve to sharpen your attention and awaken some curiosity in them. Again and again the net sweeps among the weed, or dredges the bottom of the pond, bringing up mud, stones, sticks, with a fish, worms, molluscs, and tritons. The fish we must secure, for it is a stickleback--a pretty and interesting inhabitant of an aquarium, on account of its nest-building propensities. We are surprised at a fish building a nest, and caring for its young, like the tenderest of birds (and there are two other fishes, the Goramy and the Hassar, which have this instinct); but why not a fish, as well as a bird? The cat-fish swims about in company with her young, like a proud hen with her chickens; and the sun-fish hovers for weeks over her eggs, protecting them against danger.