any

every tree and shrub, low or high. Examine tuft of leaves or protuberance on twig or trunk. Pass over nothing that at all suggests what you are in search of. Sometimes it is a good plan to study a clump of bushes or a tree from one direction and then slowly circle it so that the light will be thrown on the leaves and limbs from various angles.

If you are in the street, you may collect a small crowd anxious to see "what the gink is rubberin' at," but a true explorer never pays any attention to little things like that. A vacant city lot which has many or few bushes, stumps with sprouts springing from them, little, weazened trees that almost apologize for living, sometimes yield surprising finds. A lane in the suburbs with trees and bushes on either side furnishes good hunting-ground. If there is a wall on either side with a vine of some sort growing upon it, you may find that careful search will reveal brown, baggy bunches that prove to be cecropia cocoons. Patches of scrub white-birch or spicebush should always be carefully examined, as such places often harbor many cocoons.

Cocoons may be hunted for at any time after the spinning season until the warm Springtime weather causes the moths to emerge from the cocoons. As soon as possible after the falling of the leaf is the best time, as certain birds tear apart the cocoons and eat the tender pupa within. Places in the cities and suburban towns are usually more productive of

results to the cocoon-hunter, not necessarily because there are more cocoons, but because the cocoons are more in view and closer together on account of there being fewer trees and shrubs to attract the female moth as it lays its eggs. Almost the best place of all is a field with numerous scattered clumps of willow, maple, spice-bush, or alder; these usually are small and accessible. The adult moth, on its egglaying mission, seems to find dense vegetation a hindrance and hence avoids it.

The caterpillars probably do not stay many feet from the spot where they hatched from the egg; indeed, the worm may pass all stages of its lifehistory and spin its cocoon on a single shrub. Sometimes such unpromising spots as backyards are well worthy of search. The egg-laying function of the moth is compulsive and the eggs must be laid wherever the parent may chance to be at the proper time of depositing them. It has from two hundred to six or eight hundred eggs to dispose of in a comparatively short time, and cannot afford to be too nice as to the character of the place where it deposits them.

The American silkworm caterpillars have various parasitical enemies, particularly varieties of the ichneumon-flies. The adult parasite lays its eggs on the body of the caterpillar; there hatch out and the tiny worms proceed to eat their way into the body of their host, which soon may die. Or the cater

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pillar may live long enough to perform its functions of spinning but then dries up and dies. Or the parasite may construct a peculiar kind of cocoon within the larger one spun by the host; such specimens are interesting to the scientist but valueless to the one who wishes to rear caterpillars from the egg. As a rule, specimens which have not pupated are easily distinguishable from good ones. The silk of such cocoons is thinner, and when the cocoon is shaken close to the ear a peculiar dry rattle is heard; a good specimen when similarly treated gives a characteristic, unmistakably solid thud. Those specimens in which parasites have pupated are not thus distinguishable; only by opening the cocoon and examining the contents can the counterfeit be detected. It is not well to disturb the pupa in this way; it is better to watch carefully for the emergence of the wasp-like ichneumonides, which should be destroyed when they are perceived.

While the idea of collecting the cocoons and of getting a supply of eggs from the moths is unmistakably the best plan, do not be in despair if your cocoon-hunt is unsuccessful. You may be able to capture one or more fertile females in the Spring, which will supply you eggs from which enough caterpillars will hatch to keep you sufficiently busy. For this variety of "bug-hunting" you will need a net of some light mosquito-mesh, with tin or paper boxes in which to stow away your captures.