1.Children who are fond of country walks，and who use their eyes well，will be sure to notice in early spring little lumps of jelly floating on some pond by the roadside.This jelly-like stuff consists of a number of frogs’eggs or “spawn.”If we look at the spawn very closely，we shall see a great many black specks.Each of these specks is the centre of an egg.
2.Let us return to the pond a month later.The spawn has gone，for all the eggs have burst open，and out of each one has come a little animal called aEGGS OF FROG（青蛙卵）tadpole.Tadpoles are very funny-looking little things about an inch in length，each with a large round black head and a flat tail.They swim about in the water by the help of their tail，and they are very much like little fishes in many other ways.
3.They have little pink gills，which stick out on each side of their head.By its gills the tadpole can breathe the air which is dissolved in the water，just as a fish does.The little creature soon dies if it is taken out of the water，for it cannot breathe the air as we do.Each tadpolehas a mouth with tiny teeth to gnaw theGROWTH OF TADPOLE（蝌蚪的生长）plants on which it feeds.
4.It is very curious to watch the changes that take place in the tadpole during the three months or so that it lives in the water.The gills become covered over，and lungs grow inside the body to do their work.The tail becomes shorter，and near it two legs break through the skin.Then other two legs come out nearer to the head.
5.The tadpole is now able to walk，and to breathe the air just as we do，so it crawls out of the pond and lives in the damp grass.Its tail becomes still shorter，and soon disappears.Now it is no more a tadpole；it has become a young frog.
6.Every one must have seen frogs jumping about in the wet grass by the roadside on a summer evening.They are quite harmless，and you may take one in your hand without any fear.But if you do pick one up to look at it，be very careful not to hurt it.
7.Look at the squat①，stumpy②body of the animal，with its very short neck and three-cornered head.The frog is about two or three inches in length，and is mottled③with brown and yellow on the back；but it is lighter in colour underneath.The skin has no fur or hair，but it is covered with a slimy fluid.
8.The two hind legs are long and Strong.Each of the hind feet has five toes，which are joined by a web.The two front legs are much shorter and weaker.The front feet have only four toes each，and they are not webbed④.The limbs of the frog remind us of those of the rabbit；for with both these animals it is the hind legs whichdo most of the work in helping them to move about.
SKELETON OF FROG
（青蛙的骨骼）
9.The frog has no tail；and although it has a backbone，it has no ribs.Its two eyes are large，and stand far out from its head.Each eye has two eyelids，the under eyelid being made of thin and clear skin.
10.The frog has a large mouth；but as it does not chew its food，it has only a few tiny teeth in its upper jaw.The tongue of the frog is most useful to the creaturein catching the flies and other small insects on which it feeds.It is joined to the lower jaw inTONGUE OF FROG（青蛙的舌头）front，and not at the back as our①Squat，short and thick.
②Stumpy，thick-set.
③Mottled，spotted；having spots or shades of different colours.
④Webbed，having the toes joined by a piece of skin between them.
tongues are.Thus the tongue of the frog lies in the mouth pointing backwards.At its tip there is a kind of sticky pad.
