Photo by L. H. Joutel] [New York. similar way. Though common and LONG-HORNED GRASSHOPPER. destructive in fields and gardens, it This insect belongs to the same family as the well-known British species. The specimen from which this photograph was taken had unfortunately (as is often the is not often seen; but if water be case) broken antenna;; they should be twice as long as the wings. thrown on the ground overnight, and a board laid over it, one or two mole-crickets are likely to be found underneath in the morning. The HOUSE-CRICKET resembles this insect in colour, but is not much more than half an inch long, and there is nothing remarkable in the structure of its legs. It is almost the only noisy insect found in English houses, and is very similar to the common cockroach in its habits, although free from the disagreeable smell which adds to the disgust the latter insect often inspires. The third species, the FIELD-CRICKET, is a smooth black insect, larger and stouter than the house-cricket. It constructs burrows in grassy places, but is not now a very common species in England. In the last two species, and many others, there is a bare space on one of the wing-cases of the male, crossed by ribs in a manner varying according to the species, which helps to produce the loud chirping for which these insects are remarkable. The LONG-HORNED GRASSHOPPERS, which form the next family, are distinguished by having four joints to their feet, a long ovipositor in the female, and very long, slender by J. Edicards] [Colesborne.antennae. The commonest species inhabiting " Photo England, and one of the largest grass- CAPE GRASSHOPPER (FEMALE). hoppers, is the GREAT GREEN GRASSHOPPER, anceThisof theinsect,male,whichis anis objectremarkableof superstitionfor the inflatedamongbladder-likethe Boers. appear-Colour,, stripes.which is found leaping about among long bright apple-green with white

1'hoto by Higldey.

EGYPTIAN LOCUST.

A common North African species, of which specimens occasionally visit England.

Photo by Highley.

EGYPTIAN LOCUST.

This figure shows the upper surface of the specimen represented in the preceding photograph. 693

of the World694 The Living Animals

grass and low bushes, especially in the south of England. It is about 2 inches in length. Among the foreign species of this rather extensive family, we may mention some green or reddish South American species, with a large round spot on the hind wings, not unlike those seen in the peacock-butterfly.

The last family includes the SHORT-HORNED GRASSHOPPERS, or TRUE LOCUSTS, so very destructive in many countries, though the real MIGRATORY LOCUSTS are only casual visitors to England, the native British species being all small insects, found among grass, and doing but little damage. The commonest of the Migratory Locusts visiting Britain is the KED-LEGGED LOCUST, which expands from 2 to 4 inches, and has grey wing-cases varied with brown, pale green hind wings, and red hind shanks, with white black-tipped spines. Another species, the EGYPTIAN LOCUST, more rarely met with, has brown fore wings, and grey hind wings, crossed by a broad blackish band. Two photographs are given on page 693 of a specimen brought to England among vegetables in the spring of 1901. Many foreign locusts, large and small, have beautiful red or blue hind wings, and some of these are common on the Continent, though not in England; those found in Europe are comparatively small, measuring only 1 or 2 inches across the wing-cases; but some of the great South American locusts measure as much as 7 or 8 inches in expanse. However, some of the smaller species, such as the CYPRIAN LOCUST and the EOCKY MOUNTAIN LOCUST, which measure less than 2 inches across the wing-cases, are much more destructive than the large species. A real invasion of locusts is a terrible calamity, for the insects fly like birds, but in vast flocks, and

Photos by W. L. II. Duckworth'] [Cambridge. devour every scrap of vegetation where WART-EATING GRASSHOPPER (TWO VIEWS). flight, two Used by Swedish peasants to bite off their warts. they settle. Sometimes a or three miles broad, continues to fly steadily over the same spot fdr hours together. Sometimes flocks perish at sea, and are cast up on the beach in heaps like sand-hills, extending for a distance of forty or fifty miles. Nor are the young locusts less destructive before they acquire wings; for they march across a district in such numbers as to extinguish fires, fill up trenches, and overcome all similar obstacles placed in it is well said of a visitation of locusts, " The landtheir way by sheer force of numbers; and is as the Garden of Eden before them, and behind is a desolate wilderness."

695

NERVE-WINGED OR LACE-WING ED INSECTS, OR DRAGON-FLIES AND THEIR RELATIVES.

BY THE REV. THEODORE WOOD, F.E.S.

THE Nerve-winged Insects owe their title to the peculiar character of their wings, the horny veins which form the framework of those organs being multiplied and sub-divided to such an extent that they assume the appearance of exceedingly delicate network.

These insects fall naturally into two great groups, in one of which the chrysalis, or pupa, is active, and continues to take food like the grub, while in the other it is passive and helpless, like that of a butterfly or a moth. first division are the Dragon-flies, which owe their Prominent among the members of the title partly to their extreme voracity, and partly to the fact that they feed entirely upon living insects, which they pursue through the air. They are exceedingly swift of wing, and may be seen hawking over ponds and streams on any fine day throughout the summer and early autumn. The earlier part of their lives is spent in the water, in which the eggs are laid by the parent insect. The grubs are usually of a dull grey or brownish-green colour, and are remarkable for a curious organ known as the "mask," which partly covers the lower surface of the head. This apparatus consists of two joints, which fold upon one another, but can be extended at will, the one farthest from the head terminating in a pair of large and powerful jaws. When the grub perceives an insect-victim, it swims cautiously beneath, and seizes isit by means of these jaws. The "mask" then folded, and the prisoner drawn down within reach of the mandibles, by means of which it is speedily devoured.

The method of swimming practised by the dragon-fly grub is also very curious. Through the centre of the body runs a longitudinal tube, terminating in a circular orifice, closed by means of five tightly fitting valves. These valves, which together form a sharp spike when closed, can be separated at Photo by W. P. Dando, F.Z.S.'] [Regent's Park. will. When the insect wishes to swim, it fills the tube with water, and then squirts DRAGON-FLY. do although Horse-stingers," they insects harmless, except to the contents forcibly out, the result being not Thesesting horsesinsects; arein oftenfact, theyknownareasperfectly" that it is driven swiftly forwards by the smaller and weaker than themselves. reaction. is very much like the grub, with the exception that the The pupa of the dragon-fly rudiments of the future wings may be seen on the back.

About forty species of these insects are found in the British Islands, of which the GREAT is 3 inches in length, while the extended DRAGON-FLY is a well-known example. The body wings measure about 4 inches from tip to tip. In colour it is light rusty brown, with a is perfectly harmless, notwithstanding its few pale markings. The " HORSE-STINGER " which popular title is also common, and may be recognised at once by its flat dull yellow body, which becomes blue in the fully developed male. In the graceful and beautiful DEMOISELLE is entirely green. the male is deep blue, with black patches on the wings, while the female

Allied to these insects is the COMMON MAY-FLY^ popularly supposed to live for one day only. As a matter of fact, however, it spends a couple of years in the grub and pupa states, inhabiting burrows in the banks of ponds and streams. These burrows are curved, and have

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two entrances, one above the other, so that the insect can pass in and out with perfect ease. The May-fly is also remarkable for the fact that the perfect insect changes its skin shortly after reaching maturity. Before this change takes place the female insect is the " Green Drake " of the angler; afterwards, the " Grey Drake." To this group belong also the TERMITES, or "White Ants," so exceedingly numerous in almost all the warmer parts of the world. These are social insects, living together in vast colonies, and making most wonderful nests, which consist of a vast and complicated series of chambers and passages, sheltered beneath a turreted dome of clay. In the centre is the " royal cell," inhabited by the " king " and " queen," as the perfect male and female are called. first they leave the pupal shell. These are winged when But after taking a single flight, they snap off their wings at the base, just as ants do; while for the rest of their lives they are absolute prisoners in the cell built around them by the workers. Shortly after this strange incarceration takes place, the body of the queen swells to a huge size, so that, to quote Professor Drummond, she becomes "a large, loathsome, cylindrical package, 2 or 3 inches long, in shape like a sausage, and as white as a bolster." She now begins to deposit eggs at the rate of several thousands in a day, is which are at once carried off by the workers, to whom entrusted the entire care of the helpless young. These workers, which are exceedingly numerous, also enlarge the nest from time to time, and construct tunnels of clay up the trunks and along the branches of trees, through which they may convey to the nurseries in security the gums and decaying wood for the nutriment of the young. I'koto by W. P. Dando, F.Z.S., Regents Park. A fourth form of insect is also found in the termites' QUEEN TERMITE. nest, known as the " Soldier." The head is much larger Her huge white body is full of epgs, of which she and the jaws are much longer and stronger than those lays thousands every day. of the worker, and the sole function appears to be to defend the nest when attacked. Both soldier and worker, apparently, proceed from the same eggs which produce the king and queen, the difference in development being probably due as in the hive-bee to the character of the food with which the young are supplied.

Photo by W. P. Dando, F.Z.S.] [Regent's Park. TERMITES. The perfect male and female are winged, the " worker " and the " soldier " being more like grubs than perfect insects.

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