2. Ask the students to bring to school as many other kinds of legume roots as they can find, so that the other members of the school can see them.

of water and four parts of formalin. Then seal tightly. If well sealed, the

great majority are either harmless or helpful to mankind.

Certain kinds of bacteria in the soil are good friends to the farmer.

One kind lives on the roots of legumes and causes the nodules, or tubercles. In some way these bacteria take nitrogen from the air so that it becomes available for the growth of plants. The larger part of the air is nitrogen, but none of the higher plants can take nitrogen from the air. They can only use it when it is combined with other things. The air between the particles of the soil furnishes the nitrogen for the bacteria on the legumes. These bacteria do not live on the roots of any common plants except legumes.

The reason why this is so important a subject is because nitrogen is the most expensive thing that farmers buy in fertilizers. They now pay about twenty cents a pound for the amount of actual nitrogen in a fertilizer.

Sometimes the bacteria are not in the soil, so that the legumes do not have the tubercles. Only when a new kind of legume is introduced are the bacteria likely to be lacking. The majority of the soils in New York State need to be inoculated for alfalfa when it is first grown, and so far as we know all soils in the State need to be inoculated for soy beans. The best means of inoculation is to take soil from a field where the crop is inoculated and scatter on the new land. About two hundred pounds of such soil is enough for an acre. Sweet-clover soil inoculates alfalfa; so that where sweet clover is plentiful, alfalfa does not often need to be inoculated.

Words to be spelled and defined

Nodule, a little knot or lump.

Tubercle, a nodule formed within a plant or an animal by bacteria. Bacteria, microscopic plants often called microbes.

Microscopic, too small to be seen without a microscope.

Nitrogen, a gas that constitutes about four fifths of the air.

Fertilizer, a material for making land more productive.

Inoculation, infection with bacteria or some other organism; as inoculation with smallpox virus, or the adding of certain bacteria to a soil.

LEGUMES AS FOOD

We have already learned that nitrogen is one of the very important plant-foods, and that leguminous plants are able to obtain a part of their nitrogen from the air, provided the proper bacteria are present for the formation of the nodules on the roots.

All plants can take nitrogen from the compounds in the soil. Legumes are no exception. They have two ways of obtaining nitrogen, hence we shall not be surprised to learn that they contain a higher percentage of it than do other plants. A very common error is to suppose that because legumes can obtain some nitrogen from the air, they do not need much of

it in the soil or the fertilizer. Nearly all legumes require a rich soil for their successful growth. They have two ways of getting nitrogen, and can live by either way alone but need both ways in order to produce good crops. The following table shows the percentage of nitrogen and protein in a few crops. The first two are legumes.

Nitrogen does not occur in plants as an element, but as a compound. The compounds that contain nitrogen are commonly called protein; "nitrogenous compounds" would be a more accurate name. There are a number of these compounds. On the average they contain about 16 per cent of nitrogen. When a chemist determines the percentage of protein he finds the amount of nitrogen and multiplies this by six and one fourth in order to get the percentage of protein. One of the very important constituents of our food is protein. The following table gives the amount of water and protein in a few foods:

It will be seen that these legumes contain over twice as much protein as wheat flour. Peas and beans may be used to replace the protein of meat to a considerable extent. They are a little harder to digest, and therefore are not ordinarily used in very large quantities except by persons who have outdoor work.

The most important way in which legumes furnish protein for human food is indirectly. Of course an animal that produces lean meat, eggs, milk, or other product that is high in protein, must have much protein in its food. Alfalfa and clover hay are the indirect source of much of the protein in our milk and meat.

Problem 1. What percentage of nitrogen is there in each of the foods in Table 2?

Problem 2. Another way to compare these is on the basis of dry matter. Green peas contain 81.8 per cent of water and 3.4 per cent of protein, or 18.2 per cent of dry matter of which 18.7 per cent is protein. How much dry matter is there in each of the other foods? What percentage of the dry matter is protein?

Protein is only one of several important constituents of food.

SWEET PEAS AND GARDEN PEAS

THE EDITORS

The relationships of plants are always interesting to children. In studying the pea, have the boys and girls gather some material from which they may be able to trace the likenesses of peas to locust, clover, alfalfa, beans, lupine, or other plants in the family.

If there is interest in these plants have a lesson on the blossom of the pea, calling attention to the parts (see figure on page 1384). The pupils can easily distinguish the upper petal, called the banner, or standard; the two side petals, called the wings; and the two lower ones, grown together and called the heel. They will see the ten stamens, nine united and one free, and the single pistil.

The compound leaves are interesting, and the tendrils which reach out for support for the plant. Observations may be made on the pods, and the way in which sweet peas send out the seeds.

In rural districts there are many lovers of flowers who grow sweet peas successfully. A visit to a good garden to see the many differentcolored sweet peas, and to learn how they were grown, will be of interest to the children. If gypsophila is also grown in the same garden, the teacher will have an opportunity to show what a beautiful combination of cut flowers may be made with sweet peas and gypsophila.

It will be well to make a study of garden peas grown in the neighborhood. What varieties are most popular? What succession is advisable in order to extend the season of peas for the home table? Why not have a small crop of peas grown at school this year, even if it has to be harvested in vacation? Many rural teachers have found that it is not difficult to encourage some pupil or pupils to complete the work of a simple school garden, and the cultivation of a small crop at school often leads to greater interest in the larger crop at home.

RYE

E. G. MONTGOMERY

Rye is more like wheat than any other cereal. The plant is similar, but the head is more slender. It differs principally in being hardier, and not only will grow in colder countries than wheat, but also does well on poorer soils. Rye

In

In

flour makes good bread, but the bread is darker in color and more moist than wheat bread. America we eat wheat bread principally, but in certain countries, as Germany and Russia, more rye bread is eaten than wheat bread. Germany three times as much rye is raised as wheat. In NewYork State rye is raised in a small way for various purposes. It is usually sown in the fall, at any time from August to October. It makes a full growth, and is well rooted so that it is ready to make a very rapid growth in the

following spring. It

Rye

grows faster and ripens earlier than any other grain, usually being ready to harvest about the first of July.

Because of its rapid early growth, farmers often grow rye for green manure. That is, it is sown in the fall after a crop of grain has been harvested, and makes a heavy growth which is plowed under the next spring in time to plant potatoes or corn.

Rye is also grown for the straw, especially in the vicinity of large cities. such as New York. The straw is valuable for bedding in barns, also