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bodies. They cut numerous galleries between the wood and bark, invading both parts at the same time. Each species draws the same design, so that we can always determine the workman by his work.
11. A pair of these insects always enter the tree together, and soon hollow out a central gallery, from which they pierce from two to four holes to air their dwelling and give them light. The eggs are laid all along this chamber, from fifty to one hundred in number. As soon as the larves are hatched, they hollow out other little grooves, so that often they cover the whole surface of the tree. As soon as these insects arrive at their perfect state, they bore holes at the end of their chamber and escape. The great pine- gnawer ravages the forests of fir-trees in such manner that often not even a single tree escapes.
12. Each organ has its enemy. Our apples and plums are gnawed and injured by worms, the progeny of wingless insects. The curculio is a hard shelled beetle, with the forepart of the head prolonged into a broad muzzle or a long slender snout, at the end of which is the mouth armed with small horny jaws. The Plum - Weevil is about the fifth of an inch long, exclusive
of the snout, and, when shaken from the tree, looks like a dried bud. The curculio makes a crescent-shaped incision in the surface of the plum and lays an egg in the wound. It goes from plum to plum until its stock is exhausted; when the beetles are plentiful, not a plum escapes from being stung. A whitish grub without feet is hatched from the egg. This grub burrows to the very stone of the fruit.
13. The Hessian Fly is an enemy of wheat fields and two broods appear annually, one in spring and one in autumn. The eggs are laid upon the young blades of wheat and hatch in about four days. The larves crawl down the leaf and work their way between it and the stalk until they come to a joint underground, where they remain until they are grown. They suck the sap, and when several fix themselves upon the same stalk, it soon withers. In about six weeks these larves attain their full size and resemble a flax-seed. In April or May they come forth in their winged state and begin to lay their eggs, and in June or July take the flax-seed form and are ready to attack the fall wheat. It is believed that this fly was brought to this country in straw by the Hessian troops under Sir William Howe.
14. Another enemy of our grain fields is the Wheat Fly. These insects move in immense swarms, taking wing in the morning or evening twilight, or in cloudy weather, and lay their eggs in the opening flowers of the grain of barley, rye, oats and wheat. The eggs hatch in eight days and the maggots are found within the chaffy scales of the grain. They mature in about fourteen days and prey upon the wheat when in blossom or in milk. They cease eating, become torpid and shortly afterwards moult their skins and become inactive for a few days. They then descend to the ground, into which they burrow and remain for the winter.
15. If nature had not made some provision for the destruction of these and other predatory insects, they would soon destroy vegetation from the face of the earth. A hornet would drive out the inhabitants of the land. But there are also carnivorous insects, shrews, moles, hedgehogs, field mice and insectivorous birds, which destroy the grubs and catch the mature insects, just as cats catch mice. What does it mean that insects rest at noon and that moles come to the surface daily at twelve o'clock?
Spell and use in sentences :
fôr'est ers skīr'mish ers fôr'mi da ble měn'aç es
nûrs'er ies ex haust'ed prěd'a to ry cûr cū'li o
What do woodmen and foresters do in order to destroy the ravagers of the forest? What does the Pine Bombyx do?-the Tent-caterpillar ?-Dart moths ?-Canker-worms? Describe the insect which attacks the wood and bark of trees. Describe the Curculio ;-the Plum-Weevil ;-the Hessian Fly ;-the Wheat Fly.
My heart leaps up when I behold
A rainbow in the sky:
Or let me die!
William WORDSWORTH (1770-1830).
Listen to the water-mill, all the livelong day,-
Take the lesson to yourselves, loving hearts and true:
Oh! the wasted hours of life that have fleeted by!
D. C. McCALLUM.
Spell and use in sentences :
crēak'ing cēase'less lan'guid ly