[Contents]CHAPTER LIIISAP-SUCKERS“What do plant-lice eat?” asked Jules one day. “I have never seen them feeding on leaves.”“They do not feed on them,” his uncle replied; “they drink the sap through a very fine, short, pointed sucker which they carry against the breast when not in use. The insect plunges it into the plant and for whole days without moving drinks the sap at the point pricked. When this place is sucked dry it passes to another, but without much change of position. The plant-louse is a sedentary creature; to move around a stem no bigger than your little finger is for the louse a long journey fraught with perils not lightly to be faced, a few steps forward to make room in the rear for some fifty children as fast as they are brought into the world being about all that the boldest of these creatures dares to undertake. But plant-lice of the last generation of the year have wings and lay eggs which in the spring renew the race annihilated by the cold of winter. These winged lice are no timid stay-at-homes like the others: they gladly quit the natal leaf to see a bit of the world. It is their business to travel hither and yon and lay their eggs in many places so that in the following spring all plants[382]shall have their share of lice, and it is to fulfill this duty that they are expressly provided with wings. Clouds of these traveling plant-lice, dense enough to obscure the light of day, have been observed.Periodical CicadaPeriodical Cicadaa, pupa;b, cast pupa-shell;c, fully developed insect;d, punctured twig;e, two eggs. (a,b,c, natural size;d,e, enlarged.)“Many other insects have, like the plant-louse, a straight, pointed sucker which they plunge into the substance they wish to drain of its juice, and which they hold against the breast when not in use. The cicada furnishes us a very good example, as do also the large bugs found on trees and on many plants. The cabbage feeds two of them: the harlequin cabbage-bug, which is red with numerous black spots, and still another cabbage-bug of a bluish-green color with white or red spots.[383]“Bugs of this class have four wings, the upper pair covering the other pair when in repose. The forward half of each upper wing is hard like the beetle’s wing sheaths, but the other half is membranous and of fine texture. This structure makes them half sheaths for protection and half wings for flying, and it is because of this peculiarity that insects of this sort are called hemiptera, or half-winged creatures. The cicada is a half-winged insect, as is also the plant-louse, although its upper wings (I am speaking of winged plant-lice, of course), instead of being one half hard and the other half of a more delicate texture, have the same fineness and transparency throughout. But the most striking characteristic of these insects, and the one that determines their mode of life, is the beak for sucking. So we will call hemiptera all insects equipped with a pointed sucker which lies against the breast when in repose, and we will not concern ourselves with the question of wings, whether half or entirely membranous.”“Do the hemiptera form an order by themselves?” asked Jules.“They form an order in the same way that coleoptera, lepidoptera, hymenoptera, diptera, and so on, form each an order. But hemiptera do not undergo so thorough a transformation as other insects, being born with very nearly the form they will always have. The chief change consists in the growing of wings, which the insect does not have at first, but acquires later when it has attained sufficient[384]size. In some species several generations succeed one another before the winged state, which is the perfect one, is reached. Plant-lice belong to this class, the earlier generations of the year having no wings, and only the last being equipped with them.Pear-tree Flea-lousePear-tree Flea-louse(Cross shows natural size)“A hemipterous insect with habits somewhat like those of the plant louse causes considerable damage to pear-trees. It is commonly called the flea-louse of the pear, and is a small reddish insect with diaphanous wings that fold at an angle like the two sides of an acute-angled roof. It is found on pear-trees, and more rarely on apple-trees, toward the end of April. The eggs are laid one by one in slight gashes made in the leafstem by the female with a little auger situated at the end of the abdomen. The larvæ that come from these eggs grow rapidly and differ from the perfect insect only in their lack of wings. By sloughing the skin these larvæ become nymphs, short and stubby and already having on each side a rudimentary wing. In its final form the insect acquires perfect wings. In all three of its successive stages the insect plunges its sucker into the tender bark, or into the leaves, and sucks the sap. The best way to destroy these creatures is to use a hard bristle brush on those parts of the bark where they are to be found in multitudes.”[385]
[Contents]CHAPTER LIIISAP-SUCKERS“What do plant-lice eat?” asked Jules one day. “I have never seen them feeding on leaves.”“They do not feed on them,” his uncle replied; “they drink the sap through a very fine, short, pointed sucker which they carry against the breast when not in use. The insect plunges it into the plant and for whole days without moving drinks the sap at the point pricked. When this place is sucked dry it passes to another, but without much change of position. The plant-louse is a sedentary creature; to move around a stem no bigger than your little finger is for the louse a long journey fraught with perils not lightly to be faced, a few steps forward to make room in the rear for some fifty children as fast as they are brought into the world being about all that the boldest of these creatures dares to undertake. But plant-lice of the last generation of the year have wings and lay eggs which in the spring renew the race annihilated by the cold of winter. These winged lice are no timid stay-at-homes like the others: they gladly quit the natal leaf to see a bit of the world. It is their business to travel hither and yon and lay their eggs in many places so that in the following spring all plants[382]shall have their share of lice, and it is to fulfill this duty that they are expressly provided with wings. Clouds of these traveling plant-lice, dense enough to obscure the light of day, have been observed.Periodical CicadaPeriodical Cicadaa, pupa;b, cast pupa-shell;c, fully developed insect;d, punctured twig;e, two eggs. (a,b,c, natural size;d,e, enlarged.)“Many other insects have, like the plant-louse, a straight, pointed sucker which they plunge into the substance they wish to drain of its juice, and which they hold against the breast when not in use. The cicada furnishes us a very good example, as do also the large bugs found on trees and on many plants. The cabbage feeds two of them: the harlequin cabbage-bug, which is red with numerous black spots, and still another cabbage-bug of a bluish-green color with white or red spots.[383]“Bugs of this class have four wings, the upper pair covering the other pair when in repose. The forward half of each upper wing is hard like the beetle’s wing sheaths, but the other half is membranous and of fine texture. This structure makes them half sheaths for protection and half wings for flying, and it is because of this peculiarity that insects of this sort are called hemiptera, or half-winged creatures. The cicada is a half-winged insect, as is also the plant-louse, although its upper wings (I am speaking of winged plant-lice, of course), instead of being one half hard and the other half of a more delicate texture, have the same fineness and transparency throughout. But the most striking characteristic of these insects, and the one that determines their mode of life, is the beak for sucking. So we will call hemiptera all insects equipped with a pointed sucker which lies against the breast when in repose, and we will not concern ourselves with the question of wings, whether half or entirely membranous.”“Do the hemiptera form an order by themselves?” asked Jules.“They form an order in the same way that coleoptera, lepidoptera, hymenoptera, diptera, and so on, form each an order. But hemiptera do not undergo so thorough a transformation as other insects, being born with very nearly the form they will always have. The chief change consists in the growing of wings, which the insect does not have at first, but acquires later when it has attained sufficient[384]size. In some species several generations succeed one another before the winged state, which is the perfect one, is reached. Plant-lice belong to this class, the earlier generations of the year having no wings, and only the last being equipped with them.Pear-tree Flea-lousePear-tree Flea-louse(Cross shows natural size)“A hemipterous insect with habits somewhat like those of the plant louse causes considerable damage to pear-trees. It is commonly called the flea-louse of the pear, and is a small reddish insect with diaphanous wings that fold at an angle like the two sides of an acute-angled roof. It is found on pear-trees, and more rarely on apple-trees, toward the end of April. The eggs are laid one by one in slight gashes made in the leafstem by the female with a little auger situated at the end of the abdomen. The larvæ that come from these eggs grow rapidly and differ from the perfect insect only in their lack of wings. By sloughing the skin these larvæ become nymphs, short and stubby and already having on each side a rudimentary wing. In its final form the insect acquires perfect wings. In all three of its successive stages the insect plunges its sucker into the tender bark, or into the leaves, and sucks the sap. The best way to destroy these creatures is to use a hard bristle brush on those parts of the bark where they are to be found in multitudes.”[385]
CHAPTER LIIISAP-SUCKERS
“What do plant-lice eat?” asked Jules one day. “I have never seen them feeding on leaves.”“They do not feed on them,” his uncle replied; “they drink the sap through a very fine, short, pointed sucker which they carry against the breast when not in use. The insect plunges it into the plant and for whole days without moving drinks the sap at the point pricked. When this place is sucked dry it passes to another, but without much change of position. The plant-louse is a sedentary creature; to move around a stem no bigger than your little finger is for the louse a long journey fraught with perils not lightly to be faced, a few steps forward to make room in the rear for some fifty children as fast as they are brought into the world being about all that the boldest of these creatures dares to undertake. But plant-lice of the last generation of the year have wings and lay eggs which in the spring renew the race annihilated by the cold of winter. These winged lice are no timid stay-at-homes like the others: they gladly quit the natal leaf to see a bit of the world. It is their business to travel hither and yon and lay their eggs in many places so that in the following spring all plants[382]shall have their share of lice, and it is to fulfill this duty that they are expressly provided with wings. Clouds of these traveling plant-lice, dense enough to obscure the light of day, have been observed.Periodical CicadaPeriodical Cicadaa, pupa;b, cast pupa-shell;c, fully developed insect;d, punctured twig;e, two eggs. (a,b,c, natural size;d,e, enlarged.)“Many other insects have, like the plant-louse, a straight, pointed sucker which they plunge into the substance they wish to drain of its juice, and which they hold against the breast when not in use. The cicada furnishes us a very good example, as do also the large bugs found on trees and on many plants. The cabbage feeds two of them: the harlequin cabbage-bug, which is red with numerous black spots, and still another cabbage-bug of a bluish-green color with white or red spots.[383]“Bugs of this class have four wings, the upper pair covering the other pair when in repose. The forward half of each upper wing is hard like the beetle’s wing sheaths, but the other half is membranous and of fine texture. This structure makes them half sheaths for protection and half wings for flying, and it is because of this peculiarity that insects of this sort are called hemiptera, or half-winged creatures. The cicada is a half-winged insect, as is also the plant-louse, although its upper wings (I am speaking of winged plant-lice, of course), instead of being one half hard and the other half of a more delicate texture, have the same fineness and transparency throughout. But the most striking characteristic of these insects, and the one that determines their mode of life, is the beak for sucking. So we will call hemiptera all insects equipped with a pointed sucker which lies against the breast when in repose, and we will not concern ourselves with the question of wings, whether half or entirely membranous.”“Do the hemiptera form an order by themselves?” asked Jules.“They form an order in the same way that coleoptera, lepidoptera, hymenoptera, diptera, and so on, form each an order. But hemiptera do not undergo so thorough a transformation as other insects, being born with very nearly the form they will always have. The chief change consists in the growing of wings, which the insect does not have at first, but acquires later when it has attained sufficient[384]size. In some species several generations succeed one another before the winged state, which is the perfect one, is reached. Plant-lice belong to this class, the earlier generations of the year having no wings, and only the last being equipped with them.Pear-tree Flea-lousePear-tree Flea-louse(Cross shows natural size)“A hemipterous insect with habits somewhat like those of the plant louse causes considerable damage to pear-trees. It is commonly called the flea-louse of the pear, and is a small reddish insect with diaphanous wings that fold at an angle like the two sides of an acute-angled roof. It is found on pear-trees, and more rarely on apple-trees, toward the end of April. The eggs are laid one by one in slight gashes made in the leafstem by the female with a little auger situated at the end of the abdomen. The larvæ that come from these eggs grow rapidly and differ from the perfect insect only in their lack of wings. By sloughing the skin these larvæ become nymphs, short and stubby and already having on each side a rudimentary wing. In its final form the insect acquires perfect wings. In all three of its successive stages the insect plunges its sucker into the tender bark, or into the leaves, and sucks the sap. The best way to destroy these creatures is to use a hard bristle brush on those parts of the bark where they are to be found in multitudes.”[385]
“What do plant-lice eat?” asked Jules one day. “I have never seen them feeding on leaves.”
“They do not feed on them,” his uncle replied; “they drink the sap through a very fine, short, pointed sucker which they carry against the breast when not in use. The insect plunges it into the plant and for whole days without moving drinks the sap at the point pricked. When this place is sucked dry it passes to another, but without much change of position. The plant-louse is a sedentary creature; to move around a stem no bigger than your little finger is for the louse a long journey fraught with perils not lightly to be faced, a few steps forward to make room in the rear for some fifty children as fast as they are brought into the world being about all that the boldest of these creatures dares to undertake. But plant-lice of the last generation of the year have wings and lay eggs which in the spring renew the race annihilated by the cold of winter. These winged lice are no timid stay-at-homes like the others: they gladly quit the natal leaf to see a bit of the world. It is their business to travel hither and yon and lay their eggs in many places so that in the following spring all plants[382]shall have their share of lice, and it is to fulfill this duty that they are expressly provided with wings. Clouds of these traveling plant-lice, dense enough to obscure the light of day, have been observed.
Periodical CicadaPeriodical Cicadaa, pupa;b, cast pupa-shell;c, fully developed insect;d, punctured twig;e, two eggs. (a,b,c, natural size;d,e, enlarged.)
Periodical Cicada
a, pupa;b, cast pupa-shell;c, fully developed insect;d, punctured twig;e, two eggs. (a,b,c, natural size;d,e, enlarged.)
“Many other insects have, like the plant-louse, a straight, pointed sucker which they plunge into the substance they wish to drain of its juice, and which they hold against the breast when not in use. The cicada furnishes us a very good example, as do also the large bugs found on trees and on many plants. The cabbage feeds two of them: the harlequin cabbage-bug, which is red with numerous black spots, and still another cabbage-bug of a bluish-green color with white or red spots.[383]
“Bugs of this class have four wings, the upper pair covering the other pair when in repose. The forward half of each upper wing is hard like the beetle’s wing sheaths, but the other half is membranous and of fine texture. This structure makes them half sheaths for protection and half wings for flying, and it is because of this peculiarity that insects of this sort are called hemiptera, or half-winged creatures. The cicada is a half-winged insect, as is also the plant-louse, although its upper wings (I am speaking of winged plant-lice, of course), instead of being one half hard and the other half of a more delicate texture, have the same fineness and transparency throughout. But the most striking characteristic of these insects, and the one that determines their mode of life, is the beak for sucking. So we will call hemiptera all insects equipped with a pointed sucker which lies against the breast when in repose, and we will not concern ourselves with the question of wings, whether half or entirely membranous.”
“Do the hemiptera form an order by themselves?” asked Jules.
“They form an order in the same way that coleoptera, lepidoptera, hymenoptera, diptera, and so on, form each an order. But hemiptera do not undergo so thorough a transformation as other insects, being born with very nearly the form they will always have. The chief change consists in the growing of wings, which the insect does not have at first, but acquires later when it has attained sufficient[384]size. In some species several generations succeed one another before the winged state, which is the perfect one, is reached. Plant-lice belong to this class, the earlier generations of the year having no wings, and only the last being equipped with them.
Pear-tree Flea-lousePear-tree Flea-louse(Cross shows natural size)
Pear-tree Flea-louse
(Cross shows natural size)
“A hemipterous insect with habits somewhat like those of the plant louse causes considerable damage to pear-trees. It is commonly called the flea-louse of the pear, and is a small reddish insect with diaphanous wings that fold at an angle like the two sides of an acute-angled roof. It is found on pear-trees, and more rarely on apple-trees, toward the end of April. The eggs are laid one by one in slight gashes made in the leafstem by the female with a little auger situated at the end of the abdomen. The larvæ that come from these eggs grow rapidly and differ from the perfect insect only in their lack of wings. By sloughing the skin these larvæ become nymphs, short and stubby and already having on each side a rudimentary wing. In its final form the insect acquires perfect wings. In all three of its successive stages the insect plunges its sucker into the tender bark, or into the leaves, and sucks the sap. The best way to destroy these creatures is to use a hard bristle brush on those parts of the bark where they are to be found in multitudes.”[385]