Our Common Insects - Part 16
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Part 16

[Ill.u.s.tration: 216 Pine Weevil and Young.]

The housewife must now guard against the intrusion of Clothes moths (Tinea), while many other species of minute moths (Tineids) and of Leaf-rollers (Tortricidae) will be flying about orchards and gardens just as the buds are beginning to unfold; especially the Coddling moth (Carpocapsa pomonella). On warm days myriads of these and other insects may be seen filling the air; it is the busiest time of their lives, as all are on errands of love to their kind, but of mischief to the agriculturist.

When the May Flower--"O commendable flowre and most in minde"--blooms, and the willows hang out their golden catkins, we shall hear the hum of the wild bee, and the insect hunter will reap a rich harvest of rarities. Seek now on the abdomen of various wild bees, such as Andrena, for that most eccentric of all our insects, the Stylops Childreni. The curious larvae of the Oil beetle may be found abundantly on the bodies of various species of Bombus, Andrena and Halictus, with their heads plunged in between the segments of the bee's body.

[Ill.u.s.tration: 217. The Comma b.u.t.terfly.]

[Ill.u.s.tration: 218. Tachina.]

The beautiful moth, Adela, with its immensely long antennae, may be seen, with other smaller moths, feeding on the blossoms of the willow. The Ants wake from their winter's sleep and throw up their hillocks, and the "thriving pismire" issues from his vaulted galleries constructed in some decaying log or stump, while the Angle worms emulate late their six-footed neighbors. During the mild days of March, ere the snow has melted away--

"The dandy b.u.t.terfly, All exquisitely drest,"

will visit our gardens. Such are various kinds of Vanessa and Grapta (Fig. 217, G. c-argenteum[30]). The beautiful Brephos infans flies before the snow disappears.

"The Gnat, old back-bent fellow, In frugal frieze coat drest,"

will celebrate the coming of Spring, with his choral dance. Such is Trichocera hyemalis, which may be seen in mult.i.tudes towards twilight on mild evenings. Many flies are now on the wing, such as Tachina (Fig.

218) and its allies; the four spotted Mosquito, Anopheles quadrimaculatus, and the delicate species of Chironomus, whose males have such beautifully feathered antennae, a.s.semble in swarms. Now is the time for the collector to turn up stones and sticks by the river's side and in gra.s.sy damp pastures, for Ground beetles (Carabidae), and to frequent sunny paths for the gay Cicindela and the Bombylius fly, or fish in brooks and pools for water beetles and various larvae of Neuroptera and Diptera; while many flies and beetles are attracted to freshly cut maples or birches running with sap; indeed, many insects, rarely found elsewhere, a.s.semble in quant.i.ties about the stumps of these trees, from which the sap oozes in March and April.

In April the injurious insects in the Northern States have scarcely begun their work of destruction, as the buds do not unfold before the first of May. We give an account, however, of some of the beneficial insects which are now to be found in gra.s.s-lands and in gardens. The farmer should know his true insect friends as well as his insect foes.

We introduce to our readers a large family of ground-beetles (Carabidae, from Carabus, the name of the typical genus) which prey on those insects largely injurious to crops. A study of the figures will familiarize our readers with the princ.i.p.al forms. They are dark-colored, brown or black, with metallic hues, and are seen in spring and throughout the summer, running in gra.s.s, or lurking under stones and sticks in damp places, whence they sally forth to hunt by night, when many vegetable-eating insects are most active.

[Ill.u.s.tration: 219. Calosoma scrutator.]

[Ill.u.s.tration: 220. Calosoma calidum and Larva.]

The larvae are found in much the same situations as the mature beetles.

They are, elongate, oblong, and rather broad, the terminal ring of the body being armed with two h.o.r.n.y hooks, and having a single fleshy leg beneath; and are usually black in color. The larva of Calosoma (C.

calidum, Fig. 220; _a_, the beetle; and Fig. 219, C. scrutator) ascends trees to feed on caterpillars, such as the Canker worm. When about to transform to the pupa state, it forms a rude coc.o.o.n in the earth. The beetle lies in wait for its prey in shallow pits excavated in pastures.

We once saw it fiercely attack a May beetle (Lachnosterna fusca) nearly twice its size; it tore open the hard sides of its clumsy and helpless victim with tiger-like ferocity. Carabus (Fig. 221, C. serratus Say, and pupa of Carabus auronitens of Europe, after Westwood) is a closely allied form, with very similar habits.

[Ill.u.s.tration: 221. Carabus and Pupa.]

[Ill.u.s.tration: 222. Brachinus.]

[Ill.u.s.tration: 223. Casnonia.]

[Ill.u.s.tration: 224. Pangus.]

[Ill.u.s.tration: 225. Agonum.]

[Ill.u.s.tration: 226. Carabid Larva.]

A much smaller form is the curious Bombardier beetle, Brachinus (Fig.

222, B. fumans), with its narrow head and heart-shaped prothorax. It is remarkable for discharging with quite an explosion from the end of its body a pungent fluid, probably as a protection against its enemies. An allied genus is Casnonia (Fig. 223, C. Pensylvanica), which has a long neck and spotted wing covers. Figure 224, Pangus caliginosus, and figure 225, Agonum cupripenne, represent two common forms. The former is black, while the latter is a pretty insect, greenish, with purplish-red wing-covers, and black legs.

Figure 226, enlarged about three times, represents a singular larva found by Mr. J. H. Emerton under a stone early in spring. Dr. LeConte, to whom we sent a figure, supposes that it may possibly be a larva of Harpalus, or Pangus caliginosus. It is evidently a young Carabid. The under side is represented.

_The Insects of May._

During this month there is great activity among the insects. As the flowers bloom and the leaves appear, mult.i.tudes wake from their long winter sleep, and during this month pa.s.s through the remainder of their transformations, and prepare for the summer campaign. Most insects hibernate in the chrysalis or pupa state, while many winter in the caterpillar or larva state, such as the larvae of several Noctuidae and the "yellow-bear," and other caterpillars of Arctia and its allies.

Other insects hibernate in the adult or imago form, either as beetles, b.u.t.terflies or certain species of bees.

It is well known that the Queen Humble bee winters under the moss, or in her old nest. During the present month her rovings seem to have a more definite object, and she seeks some deserted mouse's nest, or hollow in a tree or stump, and there stows away her pellets of pollen, containing two or three eggs apiece, which, late in the summer, are to form the nucleus of a well-appointed colony. The Carpenter bees (Ceratina and Xylocopa, the latter of which is found in abundance south of New England) are busy in refitting and tunnelling the hollows of the grape; while the Ceratina hollows out the stem of the elder, or blackberry.

This little upholsterer bee carpets her honey-tight apartment, storing it with food for her young, and later in the season, in June, several of these cartridge-like cells, whose silken walls resemble the finest and most delicate parchment, may be found in the hollow stems of these plants. The Mason bee (Osmia) places her nest in a more exposed site, building her earthen cells of pellets of moistened mud, either situated under a stone, or in some more sheltered place; for instance, in a deserted oak-gall, ranging half a dozen of them side by side along the vault of this strange domicile. Meanwhile their more lowly relatives, the Andrena and Halictus bees, are engaged in tunnelling the side of some sunny bank or path, running long galleries underground, sometimes for a foot or more, at the farthest end of which are to be found, in summer, little earthen urn-like cells, in which the grubs live upon the pollen stored up for them in little b.a.l.l.s of the size of a pea. Later in the month, the Gall flies (Cynips), those physiological puzzles, sting the leaves of our oaks of different species, giving rise to the strange excrescences and manifold deformities which deface the stems and leaves of our most beautiful forest trees.

[Ill.u.s.tration: 227. Chrysopha.n.u.s Thoe.[31]] 31 A: The lower side of the wings is figured on the right side of this and Figs. 228 and 229.

[Ill.u.s.tration: 228. Argynnis Aphrodite.]

[Ill.u.s.tration: 229. Melitaea Phaeton.]

When the Kalmia, Rhodora, and wild cherries are in bloom, many of our most beautiful b.u.t.terflies appear; such are the different species of Chrysopha.n.u.s (Fig. 227), Lycaena, Thecla and Argynnis (Fig. 228). At this time we have found the rare larva of Melitaea Phaeton (Fig. 229) clothed in the richest red and velvety black, feeding daintily upon the hazel nut, and tender leaves of the golden rod. In June, it changes to the chrysalis state, and early in July the b.u.t.terfly rises from the cold, damp bogs, where we have oftenest found it, clad in its rich dress of velvety black and red.

Later still, when the lilac blooms, and farther south the broad-leaved Kalmia, the gaily-colored Humming Bird moth (Sesia) visits the flowers in company with the Swallow-tail b.u.t.terfly (Papilio Turnus). At twilight, the Hawk moth (Sphinx) darts noiselessly through our gardens, as soon as the honeysuckles, pinks and lilies are in blossom.

[Ill.u.s.tration: 230. D. 12-punctata.]

[Ill.u.s.tration: 231. Diabrotica vittata.]

Among the flies, mosquitoes now appear, though they have not yet, perhaps, strayed far from their native swamps and fens; and their mammoth allies, the Daddy-long-legs (Tipula), rise from the fields and mould of our gardens in great numbers.

[Ill.u.s.tration: Fig. 232. Plum Weevil and Young.]

Of the beetles, those which feed on leaves now become specially active.

The Squash beetle (Diabrotica vittata, Fig. 231, and Fig. 230, D.

12-punctata) now attacks the squash plants before they are fairly up; and the Plum weevil (Conotrachelus nenuphar, Fig. 232) will sting the newly formed fruit, late in the month, or early in June. Many other weevils now abound, stinging the seeds and fruit, and depositing their eggs just under the skin. So immense are the numbers of insects which fill the air and enliven the fields and woodlands just as summer comes in, that a bare enumeration of them would overcrowd our pages, and tire the reader.

[Ill.u.s.tration: 233. May Fly.]

A word, however, about our water insects. Late in the month the May fly (Ephemera, Fig. 233) appears, often rising in immense numbers, from the surface of pools and sluggish brooks. In Europe, whole clouds of these delicate forms, with their thin white wings, have been known to fall like snow upon the ground, when the peasants gather them up in heaps to enrich their gardens and farms.

The Case worms, or Caddis flies (Fig. 234), begin now to leave their portable houses, formed of pieces of leaves, or sticks and fine gravel, or even of sh.e.l.ls, as in an European species, and fly over the water, resting on the overhanging trees.

A few busy Mosquito Hawks, or Dragon flies (Libellula), herald the coming of the summer brood of these indefatigable friends of the agriculturist. During their whole life below the waters, these entomological Herods have slain and sucked the blood of myriads of infant mosquitoes and other insects; and now in their new world above the waters, with still more intensified powers of doing mischief, happily, however, to flies mostly obnoxious to man, they riot in bloodshed and carnage.

[Ill.u.s.tration: 234. Different Forms of Case Worms.]

This is the season to stock the fresh-water aquarium. Go to the nearest brook, gather a sprig or two of the water cress, which spreads so rapidly, a root of the eel gra.s.s, and plant them in a gla.s.s dish or deep jar. Pour in your water, let the sand and sediment settle, and then put in a few Tadpoles, a Newt (Salamander), Snails (Limnaea, Planorbis and Valvata), Caddis flies and Water beetles, together with the gatherings from a thicket of eel gra.s.s, or other submerged plants, being rich in the young of various flies, Ephemeras, Dragon flies and Water fleas (Entomostraca, Fig. 235), which last are beautiful objects for the microscope, and in a few days the occupants will feel at home, and the aquarium will be swarming with life, affording amus.e.m.e.nt and occupation for many a dull hour, by day or at night, in watching the marvels of insect transformations, and plant-growth.

Among the injurious hymenoptera, which abound late in this month, is the Rose Saw fly (Selandria rosae, Fig. 236) and S. cerasi. The eggs are then laid, and the last of June, or early in July, the slug-like larvae mature, and the perfect insects fly in July. Various Gall flies now lay their eggs in the buds, leaves and stems of various kinds of oaks, blackberries, blueberries and other plants.

[Ill.u.s.tration: 235. Water Flea.]

[Ill.u.s.tration: 236. Selandria rosae.]

Dipterous Gall flies are now laying their eggs in cereals. The Hessian fly (Cecidomyia destructor) has two broods, the fly appearing both in spring and autumn. The fly lays twenty or thirty eggs in a crease in the leaf of the young plant. In about four days, in warm weather, they hatch, and the pale-red larvae crawl down the leaf, working their way in between it and the main stalk, pa.s.sing downward till they come to a joint, just above which they remain, a little below the surface of the ground, with the head towards the root of the plant. Here they imbibe the sap by suction alone, and, by the simple pressure of their bodies become imbedded in the side of the stem. Two or three larvae thus imbedded serve to weaken the plant and cause it to wither and die. The second brood of larvae remains through the winter in the flax-seed, or puparium. By turning the stubble with the plough in the autumn and early spring, its imago may be destroyed, and thus its ravages may be checked.