The forest is the home of the snail, where these interesting little animals may be found by any one desiring a closer acquaintance. They are not generally easy to find, being mostly nocturnal in habits and remaining hidden away under leaves, stones and old logs during the daytime. On rainy days, however, they may be seen crawling about, enjoying the delicious moisture.

In our last article we reviewed a few of the most interesting families of bivalve shells, and in the present paper we desire to draw the attention of the reader to the order Pulmonata, which includes those snails breathing air by means of a modified lung. The snails differ from the clams in having the body generally protected by a spiral shell which is capable of containing the entire animal. The former have a more or less expanded creeping disk which we call a foot, a head generally separated from the body by a neck (the reader will remember that the clams are headless), and also a pair of rather long eye peduncles protruding from the top of the head, which bear at their tips the round, black eyes, and a pair of short tactile organs, or tentacles, extending from the lower part of the head. The eye peduncles are peculiar in being invertible in the same manner that a kid glove finger is pulled inside out.

The mouth is placed in the lower plane of the head and is recognized externally as a simple slit. Inside of the mouth is placed one of the most wonderful dental apparatuses known to science. This is called the radula, odontophore or toothbearer, and is a belt of chitinous, transparent, yellowish or colorless material, its upper surface being armed with numerous siliceous, teeth arranged in longitudinal and parallel rows. The radula is placed in an organ called the buccal sac and occupies a position in the sac analogous to that of the tongue in a cat or dog, viz., on the floor of the mouth. It is formed from a layer of cells in the posterior part of the buccal sac, called the radula sac, and new teeth are constantly forming here to take the place of those which have become worn by use.

The whole radula rests upon a cartilage, is strongly fastened at the anterior end, and is brought down between the two fleshy lips of the mouth where it performs a backward and forward movement, thus rasping off with the sharp teeth particles of food which have been cut into small pieces by the horny jaw. During this process the morsel of food is pressed against the top or roof of the mouth. The jaw is placed in the upper part of the mouth in front of the radula, and is frequently armed with ribs to aid in cutting or biting off pieces of food, as leaves or vegetables.

As before remarked, the radula is made up of parallel rows of teeth, the whole area being usually divided into five longitudinal rows, each row differing from the one next to it. We have first a central row, on each side of this a lateral row and finally a marginal row. Each tooth in each row is made up of different parts, a basal part attached to the radula belt and an upper part which is turned over or reflexed and bent backward so as to tear off food particles by a backward movement of the whole apparatus. This diversity of form in the teeth has led conchologists to adopt a tooth formula similar to that adopted for vertebrate animals, so that the teeth of different species can be compared and the animals classified thereby. Thus each tooth has certain prominences called cusps, which vary in size, number and position, and serve admirably to describe the different groups of snails. All the mollusca except the bivalves, are provided with this radula.

One of the most wonderful and interesting facts connected with the radula is the large number of teeth on each membrane. Thus in some species of our common snails there are seventy-one teeth in a single row, and the whole radula is made up of a hundred rows of teeth, making a grand total of seventy-one hundred teeth in the mouth of a single snail!

Land snails are found almost everywhere, in valleys, high up on mountains, and even in deserts. They may be found in the cold climate of Alaska err in the tropical zone under the equator. As a rule, they prefer moist localities, where there is an abundance of vegetation and where the ground is strewn with rotting logs, beds of decaying leaves or moss covered rocks. Open woodlands may be said to be their best habitat in the northern part of the United States.