Batrachia

(bah-tra'che-ah.) BATRACHIANS, or AMPHIB IANS. [Gr. batrachos, a frog.] (Zool.) A cla of ani-|mals comprising cold-blooded, oviparous vertebrates which are destitute of scales, and which in most cases lay their numerous eggs in the water or in damp places, and whose young hatch in an immature condition, and afterwards undergo various changes before they acquire the form of the parents. The young breathe by gills similar to those of fishes, and in most cases live in the water; but in the adult state, these animals, with few exceptions, breathe by lungs, like scaly reptiles. The B. are divided into - I. Taille (Anoura), including the families: Ranidæ, or Frogs, which have the fingers and toes free, and never dilated into adi sk; upper jaw and palate provided with teeth, and the throat of the male with vocal vesicles which communicate internally with the mouth. Their young, which when hatched are called tadpoles, have a tail, but no legs. Their tail afterwards drops off, legs are developed, the gills disappear, and lungs are substituted (Fig. 67). Having undergone this metamorphosis, they live henceforth on land. Besides the common frog, there are a great many other species, the most singular of which is that called the bull-frog (Rana pipiens), a native of the U. States. This animal, when the limbs are extended, measures nearly two feet, the trunk of its body being about 8 inches long and 4 or 5 in breadth. It is very voracious, and frequently swallows the young of water-fowl before they have strength to shift for themselves. Its croaking is so loud as 1 2 to resemble the roaring of a bull heard at a distance, whence its name.-Hyloidæ, comprising frogs 3 which have the extremities of the toes and fingers enlarged into a disk or viscous pellet which enables them to adhere to the sur-5 face of bodies. 0 They inhabit trees, shrubs, and plants, except in Fig. 67.- CHANGES IN THE FORM OF A the breeding sea-BATRACHIAN - THE FROG - FROM son, when they THE TIME OF HATCHING. resort to the water. The Tree-frog, or Tree-toad, of the Middle States (Hyla versicolor), is 2 inches long, color varying from palest ash to dark brown.-Bufonide, the Toads, which have a thick squat body, covered with warts or tubercles, and a fetid but not poisonous milky juice exuding from a protuberance, studded with pores, behind each eye. They are capable of living a long time without food, and confer a great benefit upon the farmer and gardener by destroying insects. The common toad of the U. States (Bufo American us) is 22 inches long. In spring, when it resorts to the pools to lay its eggs, its prolonged trill is heard day and night. II. Tailed B. (Urodela),have a tail at all periods of life, and generally four feet. The body is long, round, and covered with skin adherent to the muscles. The families are: Sal am and ridæ, comprising Salamanders proper and the Tritons. More than 20 species are found in the U. States. In their adult state, most Salamanders live upon the land, approaching the water only at the season in which they lay their eggs. They live in cold damp places, avoiding the heat of the sun; yet ignorance and superstition have ascribed to them the power of resisting fire. The Tritons have the tail compre ed, and are entirely aquatics.-Amphiumide, are said to be destitute of gills at all periods of their existence, and breathe by means of branchial orifices at the sides of the neck. The Congo Snake (Amphiuma me aus), of the Southern States, is about 28 inches long, color bluish black, and lives in muddy waters.- Sirenidæ, have permanent external branch ise that occur in tufts, covering the branchial orifices. The Siren or Mud-eel (Siren lacertina), of S. Carolina, attains the length of24 inches; color above nearly black, with numerous light spots. It lives in mud, and is common in the ditches of rice-fields. The Axoloff of Mexico (gen. Siredom) is abt. 8 ins. long, and every way similar in form to young aquatic Salamanders. It is eaten by the Mexicans. [s. 78]