_Rana clamata_, the lusty croaker of the summer pond, is our most familiar species. He may be recognized by the colors of his dress, in which green, bronze, gold and silver play important parts, and by the ear-splitting character of his vocal intonations. The glandular ridges down the skin of his back, together with his strange coloration, singularly fit him for his home. Imitations of the stems of plants are seen in the darker ridges, and their leafage in the green color of his coat. The silver of his vest has the glimmer of the water in which he bathes, and the moist earth seems to have left its stain upon his brownish feet and markings, while the yellow of the several badges that adorn his person in being like the stamens and pistils of the surrounding flowers, and of the hue of many buds and blossoms, adds largely to his protective display. Thus is the frog in his natural haunts protected by his garments, and, unless he stirs or is betrayed by his full, bright eyes or the palpitation of his breast, he is not likely to be observed. Four fingers or toes are found upon the anterior extremities, while those of the posterior are five in number and webbed. The front legs are much shorter, smaller and weaker than the hind ones, which are largely developed, and thus serviceable in swimming and leaping. Though the frog is possessed of a back-bone, yet he has no ribs. Being ribless, he cannot expand and contract his chest in breathing, but must swallow what air he requires. In swallowing the air he must close the mouth and take the air in only by the nostrils; therefore, oddly enough, if his mouth is forcibly kept open, he will smother. The frog’s breathing, a fact not generally known, is partly through his skin, which gives off carbonic acid gas; and moisture, therefore, is just as essential to his skin as it is to the gills of a fish. Damp, rainy weather is his extreme delight. When the rain falls, out come the frogs. Their skin absorbs moisture, which is stored up in internal reservoirs, and some of this water, when these timid creatures are alarmed by being suddenly seized, is ejected, but I do not think that it is purposely so done, as the water is not, as some people have fancied, of a poisonous nature. Frogs have no poison-sacs, and in truth no weapons of any kind. Open a frog’s mouth, and you will find but a few tiny teeth in the upper jaw and palate, which are useful for the partial grinding up of horny insects. His tongue you will discover to be a very odd affair, which is fastened at the front end of the mouth, the hinder part being free and hanging down the creature’s throat. This organ is covered with a glue-like secretion. When an insect is to be captured, it is snapped forward from the mouth, and, striking the insect, which it seldom fails to do, causes it to adhere as to bird-lime.