the tubercles usually blue are sometimes black. After the last molt the caterpillar eats voraciously for perhaps two weeks or longer and then begins to spin its cocoon.

References-Moths and Butterflies, Ballard; Moths and Butterflies, Dickerson; Caterpillars and their Moths, Elliot and Soule.

Leading thought-The cecropia moth passes the winter as a pupa in a cocoon which the caterpillar builds out of silk for the purpose. In the spring the moth issues and lays her eggs on some tree, the leaves of which the caterpillar relishes. The caterpillars are large and green with beautiful blue and orange tubercles.

Method-It is best to begin with the cocoons, for these are easily found after the leaves have fallen. These cocoons if kept in the schoolroom should be thoroughly wet at least once a week. However, it is better to keep them in a box out of doors where they can have the advantage of natural moisture and temperature; and from those that are kept outside the moths will not issue, until the leaves open upon the trees and provide food for the young caterpillars when the eggs hatch.

The Cocoon

Observations-1. How does the cocoon look on the outside? What is its general shape? To what is it fastened? Is it fastened to the lower or the upper side of a twig? Are there any dried leaves attached to it? 2. Where do you find cecropia cocoons? How do they look on the tree? Are they conspicuous?

3.

Cut open the cocoon, being careful not to hurt the inmate. Can you see that it has an outer wall which is firm? What lies next to this?

Describe the wall next to the pupa. How does this structure protect the pupa from changes of temperature and dampness?

4. Is the outside covering easy to tear? enough to tear this cocoon apart?

What birds are strong

5. Are both ends of the cocoon alike? Do you find one end where the silk is not woven across but is placed lengthwise? Why is this so? Do you think that the moth can push out at this end better than at the other? Do you think the caterpillar, when it wove the cocoon, made it this way so that the moth could get out easily?

The Pupa

1. Take a pupa out of a cocoon carefully and place it on cotton in a wide-mouthed fruit jar where it may be observed. Can the pupa move at all? Is it unable to defend itself? Why does it not need to defend itself?

2. Can you see in the pupa the parts that will be the antennæ and the mouth?

3. Describe how the wing coverings look. Count the rings in the abdomen.

4. Why does the pupa need to be protected by a cocoon?

I.

The Moth

1. What is the first sign which you discover that the moth is coming out of the cocoon? Can you hear the little scratching noise? What do you suppose makes it? How does the moth look when it first comes out? If it were not all soft and wet how could it come out from so small an opening?

2.

Describe how the crumpled wings spread out and dry. How does the covering of the wings change in looks?

3. Make a water-color drawing or describe in detail the fully expanded moth, showing the color and markings of wings, body and antennæ. 4. Do the moths eat anything? Why do they not need to eat? 5. If one of the moths lays eggs, describe the eggs, noting color, size and the way they are placed.

I.

The Caterpillar

On what do you find the cecropia caterpillar feeding? Describe its actions while feeding.

2. What is the color of the caterpillar? Describe how it is ornamented.

3. Can you see the breathing pores, or spiracles, along the sides of the body? How many of these on each segment? How do they help the caterpillar to breathe?

4. Describe the three pairs of true legs on the three segments just back of the head. Do these differ in form from the prolegs along the sides of the body? What is the special use of the prolegs? Describe the propleg which is the hindmost leg of all.

5. Do you know how many times the cecropia caterpillar sheds its skin while it is growing? Is it always the same color?

6. Watch the caterpillar spin its cocoon, describe how it begins and how it acts as long as you can see it. Where does the silk come from?

THE PROMETHEA

Teacher's Story

HE promethea is not so large as the cecropia, although the female resembles the latter somewhat. It is the most common of all our giant silk-worms. Its caterpillars feed upon wild cherry, lilac, ash, sassafras, buttonwood and many other forest trees.

During the winter, leaves may often be seen hanging straight down from the branches of wild cherry, lilac and ash. If these leaves are examined, they will be found to be wrapped around a silken case containing the pupa of the promethea. It is certainly a canny insect which hides itself during the winter in so good a disguise, that only the very wisest of birds ever suspect its presence. When the promethea caterpillar begins to spin, it selects a leaf and covers the upper side with silk, then it covers the petiole with silk, fastening it with a strong band to the twig, so that not even most violent winter winds will be able to tear it off. Then it draws the two edges of the leaf about itself like a cloak as far as it will reach, and inside this folded leaf it makes its cocoon, which always has an opening in the shape of a conical valve at the upper end, through which the moth

may emerge in the spring. This caterpillar knows more botany than some people do, for it makes no mistake in distinguishing a compound leaf from a simple one. When it uses a leaflet of hickory for its cocoon, it fastens the leaflet to the mid stem of the leaf and then fastens the stem to the twig. The male pupa is much more slender than that of the female. The moths do not issue until May or June.

The moth works its way out through the valve at the top of the cocoon. The female is a large, reddish brown moth with markings resembling somewhat those of the cecropia. The male is very different in appearance; its front wings have very graceful, prolonged tips, and both wings. are almost black, bordered with ash color. The promethea moths differ somewhat in habit from the other silk-worms, in that they fly during the late afternoon as well as at night. The eggs are whitish with brown stain, and are laid in rows, a good many on the same leaf.

The caterpillars, as they hatch from the eggs, have bodies ringed with black and yellow. They are sociable little fellows and live together side by side amicably, not exactly "toeing the mark" like a spelling class, but all heads in a row at the edge of the leaf where each is eating as fast as possible. When they

are small, the caterpillars remain on the under side of the leaves out of sight. In about five days, the first skin is shed and the color of the caterpillar remains about the same. Four or five days later, the second molt occurs, and then the caterpillar appears in a beautiful bluish green costume, with black tubercles, except four large ones on the second and third segments, and one large one on the eleventh segment, which are yellow. This caterpillar has an interesting

habit of weaving a carpet of silk on which to change its skin; it seems to be better able to hold on while pushing off the old skin, if it has the silken rug to cling to. After the third molt, the color is a deeper greenish blue and the black tubercles are smaller, and the five big ones are larger and bright orange in color. After the fourth molt, which occurs after a period of about five or six days, the caterpillar appears in its last stage. It is now over two inches long, quite smooth and most prosperous looking. Its color is a beautiful, light, greenish blue, and its head is yellow. It has six rows of short, round, black tubercles. The four large tubercles at the front end of the body are red, and the large tubercle on the rear end of the body is yellow.

The cynthia is a beautiful moth which has come to us from Asia; it is very large with a ground color of olive-green, with lavender tints and

white markings; there are white tufts of hairs on the abdomen. It builds its cocoon like the promethea, fastening the petiole to the twig,

therefore the lesson indicated for the promethea will serve as well for the cynthia. The cynthia caterpillars live upon the ailanthus tree and are found only in the regions where this tree has been introduced.

References-Moths and Butterflies, Dickerson; Caterpillars and Their Moths, Elliot and Soule; Moths and Butterflies, Ballard,