Our Common Insects Part 18

[Ill.u.s.tration: 254. Apple Borer, Larva and Pupa.]

[Ill.u.s.tration: 255. Lady Bug and Pupa.]

Among beetles, the various borers, such as the Saperda, or apple tree borer (Fig. 254) are now pairing, and fly in the hot sun about trees.

Nearly each tree has its peculiar enemy, which drives its galleries into the trunk and branches of the tree. Among the Tiger beetles, frequenting sandy places, the large Cicindela generosa and the Cicindela hirticollis are most common. The grotesque larvae live in deep holes in sand-banks.

[Ill.u.s.tration: 256. Lace-winged Fly and Eggs.]

[Ill.u.s.tration: 257. Forceps-tail.]

The nine-spotted Lady Bug, Coccinella novemnotata (Fig. 255, with pupa) is one of a large group of beetles, most beneficial from their habit of feeding on the plant lice. We figure another enemy of the Aphides, Chrysopa, and its eggs (Fig. 256), mounted each on a long silken stalk, thus placed above the reach of harm.

Among other beneficial insects belonging to the Neuroptera, is the immense family of Libellulidae, or Dragon flies. The Forceps-tail, or Panorpa, P. rufescens (Fig. 257), is found in bushy fields and shrubbery. They prey on smaller insects, and the males are armed at the extremity of the body with an enormous forceps-like apparatus.

_The Insects of August._

During this month great mult.i.tudes of bugs (Hemiptera) are found in our fields and gardens; and to this group of insects the present chapter will be devoted. They are nearly all injurious to crops, as they live on the sap of plants, stinging them with their long suckers. Their continued attacks cause the leaves to wither and blight.

The grain Aphis, in certain years, desolates our wheat fields. We have seen the heads black with these terrible pests. They pierce the grain, extract the sap, causing it to shrink and lose the greater part of its bulk. It is a most insidious and difficult foe to overcome.

[Ill.u.s.tration: 258. Leaf-hopper of the Vine.]

The various leaf-hoppers, Tettigonia (Fig. 258) and Ceresa, abound on the leaves of plants, sadly blighting them; and the Tettigonias frequent damp, wet, swampy places. A very abundant species on gra.s.s produces what is called "frog's spittle." It can easily be traced through all its changes by frequently examining the ma.s.s of froth which surrounds it.

Tettigonia Vitis blights the leaf of the grape-vine. It is a tenth of an inch long, and is straw-yellow, striped with red. Tettigonia rosae, a still smaller species, infests the rose, often to an alarming extent.

The Notonecta, or water boatman, is much like a Tettigonia, but its wings are transparent on the outer half, and its legs are fringed with long hairs, being formed for swimming. It rows over the surface in pursuit of insects. Notonecta undulata Say (Fig. 259) is a common form in New England.

Another insect hunter is the singular Ranatra fusca (Fig. 260). It is light brown in color, with a long respiratory tube which it raises above the surface of the water when it wishes to breathe. This species connects the Water-boatman with the Water-skaters, or Gerris, a familiar insect, of which Gerris paludum (Fig. 261) is commonly seen running over the surface of streams and pools.

[Ill.u.s.tration: 259. Notonecta.]

[Ill.u.s.tration: 260. Ranatra.]

[Ill.u.s.tration: 261. Water Skater.]

[Ill.u.s.tration: 262. Pirates.]

Reduvius and its allies belong to a large family of very useful insects, as they prey largely on caterpillars and noxious insects. Such is Pirates picipes (Fig. 262), a common species. It is an ally of Reduvius personates, a valued friend to man, as in Europe it destroys the bed-bug. Its specific name is derived from its habit while immature, of concealing itself in a case of dust, the better to approach its prey.

[Ill.u.s.tration: 263. Phymata.]

Another friend of the agriculturist is the Phymata erosa (Fig. 263). Mr.

F. G. Sanborn states that "these insects have been taken in great numbers upon the linden trees in the city of Boston, and were seen in the act of devouring the Aphides, which have infested the shade trees of that city for several years past. They are described by a gentleman who watched their operations with great interest, as 'stealing up to a louse, coolly seizing and tucking it under the arm, then inserting the beak and sucking it dry.' They are supposed to feed also on other vegetable-eating insects as well as the plant louse."

Phytocoris lineolaris swarms in our gardens during this month. It is described and figured in "Harris's Treatise on Insects." Closely allied, though generally wingless, is that enemy of our peace, the bed-bug. It has a small somewhat triangular head, orbicular thorax, and large, round, flattened abdomen. It is generally wingless, having only two small wing-pads instead. The eggs are oval, white; the young escape by pus.h.i.+ng off a lid at one end of the sh.e.l.l. They are white, transparent, differing from the perfect insect in having a broad, triangular head, and short, thick antennae. Indeed, this is the general form of lice (Pediculus Vestimenti, and P. capitis), to which the larva of Cimex has the closest affinity. Some Cimices are parasites, infesting pigeons, swallows, etc., in this way also showing their near relation to lice.

Besides the Reduvius, the c.o.c.kroach is the natural enemy of the bed-bug, and destroys large numbers. Houses have been cleared of bugs after being thoroughly fumigated with brimstone.

During this month the ravages of gra.s.shoppers are, in the West, very wide-spread. We have received from Major F. Hawn, of Leavenworth, Kansas, a most interesting account of the Red-legged locust (Caloptenus femur-rubrum). "They commence depositing their eggs in the latter part of August. They are fusiform, slightly gibbous, and of a buff-color.

They are placed about three-fourths of an inch beneath the surface, in a compact ma.s.s around a vertical axis, pointing obliquely up and outwards, and are partially cemented together, the whole presenting a cylindrical structure, not unlike a small cartridge. They commence hatching in March, but it requires a range of temperature above 60 F. to bring them to maturity, and under such conditions they become fledged in thirty-three days, and in from three to five days after they enter upon their migratory flight.

"Their instincts are very strong. When food becomes scarce at one point, a portion of them migrate to new localities, and this movement takes place simultaneously over large areas. In their progress they stop at no obstacle they can surmount. In these excursions they often meet with other trains from an opposite direction, when both join in one.

"The insects are voracious, but discriminating in their choice of food, yet I know of no plant they reject if pressed by hunger; not even the foliage of shrubs and trees, including pine and cedar."

[Ill.u.s.tration: 264. Seventeen Year Locust, Eggs and Pupa.]

During this month the Seventeen-year locust (Cicada septendecim of Linnaeus, Fig. 264) has disappeared, and only a few Harvest flies, as the two other species we have are called, raise their shrill cry during the dog-days. But as certain years are marked by the appearance of vast swarms in the Middle States, we cannot do better than to give a brief summary of its history, which we condense in part from Dr. Harris' work.

The Seventeen-year locust ranges from South-eastern and Western Ma.s.sachusetts to Louisiana. Of its distribution west of the Mississippi Valley, we have no accurate knowledge. In Southern Ma.s.sachusetts, they appear in oak forests about the middle of June. After pairing, the female, by means of her powerful ovipositor, bores a hole obliquely to the pith, and lays therein from ten to twenty slender white eggs, which are arranged in pairs, somewhat like the grains on an ear of wheat, and implanted in the limb. She thus oviposits several times in a twig, and pa.s.ses from one to another, until she has laid four or five hundred eggs. After this she soon dies. The eggs hatch in about two weeks, though some observers state that they do not hatch for from forty to over fifty days after being laid. The active grubs are provided with three pairs of legs. After leaving the egg they fall to the ground, burrow into it, and seek the roots of plants whose juices they suck by means of their long beaks. They sometimes attack the roots of fruit trees, such as the pear and apple. They live nearly seventeen years in the larva state, and then in the spring change to the pupa, which chiefly differs from the larva by having rudimentary wings. The damage done by the larvae and pupae, then, consists in their sucking the sap from the roots of forest, and occasionally fruit trees.

Regarding its appearance, Mr. L. B. Case writes us (June 15) from Richmond, Indiana: "Just now we are having a tremendous quant.i.ty of locusts in our forests and adjoining fields, and people are greatly alarmed about them; some say they are Egyptian locusts, etc. This morning they made a noise, in the woods about half a mile east of us, very much like the continuous sound of frogs in the early spring, or just before a storm at evening. It lasted from early in the morning until evening." Mr. V. T. Chambers writes us that it is abounding in the vicinity of Covington, Kentucky, "in common with a large portion of the Western country." He points out some variations in color from those described by Dr. Fitch, from New York, and states that those occurring in Kentucky are smaller than those of which the measurements are given by Dr. Fitch, and states that "these differences indicate that the groups, appearing in different parts of the country at intervals of seventeen years, are of different varieties." A careful comparison of large numbers collected from different broods, in different localities, and different years, would alone give the facts to decide this interesting point. Mr. Riley has shown that in the Southern States a variety appears every thirteen years.

Regarding the question raised by Mr. Chambers, whether the sting of this insect is poisonous, and which he is inclined to believe to be in part true, we might say that naturalists generally believe it to be harmless.

No hemiptera are known to be poisonous, that is, to have a poison-gland connected with the sting, like that of the bee, and careful dissections by the eminent French naturalist, Lacaze-Duthiers, of three European species of Cicada, have not revealed any poison apparatus at the base of the sting. Another proof that it does not pour poison into the wound made by the ovipositor is, that the twig thus pierced and wounded does not swell, as in the case of plants wounded by Gall flies, which, perhaps, secrete an irritating poison, giving rise to tumors of various shapes. Many insects sting without poisoning the wound; the bite of the mosquito, black fly, flea, the bed bug, and other hemipterous insects, are simply punctured wounds, the saliva introduced being slightly irritant, and to a perfectly healthy const.i.tution they are not poisonous, though they may grievously afflict some persons, causing the adjacent parts to swell, and in some weak const.i.tutions induce severe sickness. Regarding this point, Mr. Chambers writes: "I have heard--not through the papers--within a few days past of a child, within some twenty miles of this place, dying from the sting of a Cicada, but have not had an opportunity to inquire into the truth of the story, but the following you may rely on. A negro woman in the employment of A. V.

Winston, Esq., at Burlington, Boone County, Ky., fifteen miles distant from here, went barefooted into his garden a few days since, and while there was stung or bitten in the foot by a Cicada. The foot immediately swelled to huge proportions, but by various applications the inflammation was allayed, and the woman recovered. Mr. Winston, who relates this, stands as high for intelligence and veracity as any one in this vicinity. I thought, on first hearing the story, that probably the sting was by some other insect, but Mr. Winston says that he saw the Cicada. But perhaps this proves that the sting is _not_ fatal; that depends on the subject. Some persons suffer terribly from the bite of a mosquito, while others scarcely feel them. The cuticle of a negro's foot is nearly impenetrable, and perhaps the sting would have been more dangerous in a more tender part." It is not improbable that the sting was made by a wasp (Stizus) which preys on the Cicada. Dr. Le Baron and Mr Riley believe the wound to be made by the beak, which is the more probable solution of the problem.

A word more about the Seventeen-year Cicada. Professor Orton writes us from Yellow Springs, Ohio, that this insect has done great damage to the apple, peach, and quince trees, and is shortening the fruit crop very materially. By boring into twigs bearing fruit, the branches break and the fruit goes with them. "Many orchards have lost full two years'

growth. Though the plum and cherry trees seemed exempt, they attacked the grape, blackberry, raspberry, elm (white and slippery), maple, white ash, willow, catalpa, honey-locust and wild rose. We have traces of the Cicada this year from Columbus, Ohio, to St. Louis. Was.h.i.+ngton and Philadelphia have also had a visitation."

[Ill.u.s.tration: 265. Hop Vine Moth and Young.]

[Ill.u.s.tration: 266. Humble Bee Parasite.]

We figure the Hop-vine moth and the larva (Fig. 265) which abound on hops the last of summer. Also, the Ilythia colonella (Fig. 266, a, pupa), known in England to be a parasite of the Humble bee. We have frequently met with it here, though not in Humble bees' nests. The larvae feed directly upon the young bees, according to Curtis (Farm Insects).

The Spindle-worm moth (Gortyna zeae), whose caterpillar lives in the stalks of Indian corn, and also in dahlias, flies this month. The withering of the leaves when the corn is young, shows the presence of this pest. The beetles of various cylindrical Bark borers and Blight beetles (Tomicus and Scolytus) appear again this month. During this month the Tree cricket (Oecanthus niveus, Fig. 267) lays its eggs in the branches of peach trees. It will also eat tobacco leaves.

[Ill.u.s.tration: 267. Tree Cricket.]

We figure (268) the moth of Ennomos subsignaria, the larva of which is so injurious to shade trees in New York City. It is a widely diffused species, occurring probably throughout the Northern States. We have taken the moth in Northern Maine. We have received from Mr. W. V.

Andrews the supposed larvae of this moth. They are "loopers," that is, they walk with a looping gait, as if measuring off the ground they walk over, whence the name "Geometers," more usually applied to them. They are rather stout, brown, and roughened like a twig of the tree they inhabit, with an unusually large rust-red head, and red prop-legs, while the tip of the body is also red. They are a little over an inch long.

[Ill.u.s.tration: 268. Ennomos subsignaria.]

_The Insects of September._

Few new insects make their first appearance for the season during this month. Most of the species which abound in the early part of the month are the August forms, which live until they are killed by the frosts late in the month. From this cause there is towards the end of the month a very sensible diminution of the number of insects.

The early frosts warn these delicate creatures of approaching cold.

Hence the whole insect population is busied late in the month in looking out snug winter quarters, or providing for the continuance of the species. Warned by the cool and frosty nights, mult.i.tudes of caterpillars prepare to spin their dense silken coc.o.o.ns, which guard them against frost and cold. Such are the "Spinners," as the Germans call them, the Silk moths, of which the American Silk worm is a fair example. The last of September it spins its dense coc.o.o.n, in which it hibernates in the chrysalis state.

The larvae of those moths, such as the Sphinges, or Hawk moths, which spin no coc.o.o.n, descend deep into the earth, where they transform into chrysalids and lie in deep earthen coc.o.o.ns.

The wild bees may now be found frequenting flowers in considerable numbers. Both s.e.xes of the Humble bee, the Leaf-cutter bee, and other smaller genera abound during the warm days.

One's attention during an unusually warm and pleasant day in this month is attracted by clouds of insects filling the air, especially towards sunset, when the slanting rays of the sun s.h.i.+ne through the winged hosts. On careful investigation these insects will prove to be nearly all ants, and, perhaps, to belong to a single species. Looking about on the ground, an unusual activity will be noticed in the ant-hills. This is the swarming of the ants. The autumnal brood of females has appeared, and this is their marriage day.