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INSECTS. First Grade.

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The first year of work with insects may well be restricted to familiarizing the pupils with the three most striking phases in the life of insects with complete metamorphosis, i. e., the larvæ, the pupæ, and the winged insects. Moths and butterflies are especially adapted for this work with the small children.

Fall work.—In September there are still many caterpillars feeding. Bring them in the schoolroom and feed them in breeding cages. For different forms of cheap breeding cages, see Insect Life, pp. 326-330; Cornell Teachers' Leaflet, No. 5 (No. XIX, this volume); Lessons in Nature-Study, p. 45.

During October many of the hairy caterpillars will be found hurrying along in quest of suitable winter quarters. These should be brought in and put in box cages having sand or dirt in the bottom. They are seeking secluded corners in which to curl up and hide during the cold weather. Some of them pass the winter in their cocoons, and some do not. Insect Life, pp. 239-241; Manual for Study of Insects, pp. 317-324; Moths and Butterflies, (b), pp. 191-198.

Bring in as many cocoons as possible. November or December, after the leaves have fallen from the trees, is the best time in which to hunt for the cocoons of Cecropia, Promethea, and Cynthia. Insect Life, pp. 194-196; Moths and Butterflies, (b), pp. 119-180.

Teach the pupils the difference between the cocoon and the pupa. The pupa is the quiescent form of the insect. The cocoon is the silken bag covering it, and is always made by the caterpillar before it changes to a pupa.

If possible bring in some butterfly larvæ. In September many may be found. The cabbage butterfly especially is always with us. Insect Life, p. 245. Also the larvæ of the black swallow-tail may be easily found. Insect Life, p. 243; Everyday Butterflies, p. 130; Moths and Butterflies, (b), p. 39.

Show the children (do not tell them) that the butterfly caterpillars do not make cocoons, but that the naked pupa is suspended by a silk button, and in some cases also by a silk thread.

Many teachers complain that but few of the moths are able to get out of the cocoons. The usual reason for this is that in the heated atmosphere of the schoolroom the cocoons become too dry. To obviate this, the cocoons should be dipped in water every week or two.

Spring work.—During the spring term use the apple-tree tent-caterpillars. Cornell Teachers' Leaflet, No. 5 (No. XIX, this volume); Moths and Butterflies, (b) p. 201. Show the four stages of the insect: egg, caterpillar, pupa, and moth. Pay especial attention to the way in which the caterpillars grow.

Summary of methods.—This whole year's work may be done with no regular "lessons," and all the time required will be the care of the breeding cages and the time given to hunting for the caterpillars and cocoons. The child's reading may be selected from the many stories of the caterpillars, moths and butterflies. Yet be very careful to make each child understand that he himself is studying out the especial story of each caterpillar and cocoon in the schoolroom.

Cornell Nature-Study Leaflets

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