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HABITS OF THE SHRILL CICADA ESSENTIALLY A SUMMER INSECT VIEWED IN ITS AUSTRALIAN HABITAT.
Birds sing best in the morning and the late afternoon ; insects sing — or make sounds — best at night. But there is one notable exception, which chooses none of these periods for its best vocal efforts, but which plys its tiny kettle drums most vigorously when the sun shines strongest, and drives all nature to a midday
siesta. That insect is the cicada. A few weeks ago those who walked at noon in the parks of the city for a brief breath of fresh air and a rest for tired eyes, before re- turning to their stuffy offices, might have seen at the base of nearly every tree, and particu- larly where the ground was bare, a series of
Cicada Pupa on Emergence from the Ground.
holes which no handy twig could bottom. These were the holes from which emerged the screech-, ing cicadas in the trees above. Passing through the parks to-day, the noise is absent ; the ci- cadas have vanished. The last spell of cooler weather has driven them away to perish miser- ably, when all other creatures have been in vigorated and refreshed. The last cicada has chirped his dying note, and now in the blazing midday heat there is peace in the trees. The cicada is essentially a Summer insect ; cold days or cold lands have no charm for him. In warm Australia there are about 120 varie- ties; in misty, foggy England there is only one. In England it chirps ; in Australia it storms ; but in the countries of the equator it shrieks a piercing note. Bates, in his 'River Amazon,' speaks of the noises of 'strange cicadas, one large, kind perched high on the trees around our little
Pupa Splitting the Skin for Perfect Insect to Emerge.
haven setting up a most piercing chirp. It be- gan with the usual jarring tone of its tribe, but this gradually and rapidly became shriller, until it ended in a long and loud note resembling the whistle of a locomotive. Half a dozen of these wonderful performers made a consider- able item in the evening concert.' LIKE A LOCOMOTIVE WHISTLE. And this is not an exaggeration, as might be supposed, but is corroborated by Mr. G. F. Mathew, who describes 'Cicada Gigas,' on the island of Tobago : — 'Suddenly, from right.
The 'Double Drummer.'
above, you hear one or two hoarse, monotonous cries, something like the croak of a tree frog, and looking upward, wonder what it can be. But wait a moment; this is merely a signal, for the next instant everywhere, above and around, you, these croaks are repeated in rapid and in- creasing succession, until they merge into a long, shrill whistle, almost exactly similar to the whistle of a locomotive. This continues for half a minute, and then abruptly terminates.' The cry, however, is taken up at a distance. 'The whistling pierces one's ears to such a de- gree that its vibrations can be felt long after it has ceased.' ABUNDANT IN AUSTRALIA. We have nothing quite so bad as that in Australia, though if one goes into the thick forest where cicadas are abundant one's ears are unpleasantly affected with the din. They are the noisiest insects on earth. No one would now class them as songsters, and it is rather surprising that the Greeks wrote poems in ap- preciation of their music, and enshrined them as symbols of that art. The noise is produced by the rapid buckling of the tiny drums, which are situated between the thorax and the base
Fore-Leg of a Pupa.
of the abdomen, and are operated by special muscles. Only the males possess these drums, a fact that was well-known to the Greeks, when they were first in the world of learning, as is shown, in the couplet written by Xenarchus (de- scribed in our Lempriere as a comic poet) : 'Happy the cicadas' lives, Since they all have voiceless wives.' AN EXTRAORDINARY LIFE. The life of the cicada is an extraordinary one— but then so is the life of every insect. The female cicada lays about 300 eggs. She has an
instrument called an ovipositor, with which she makes scratches on the bark of twigs, and in each scratch lays a small number of eggs. After she has finished her egg-laying she dies. The young ones, when hatched, are like pale fleas. They fall or jump to the ground, and, finding a suitable place, work themselves down to the roots of the trees. From this until years after- wards, when they return to the open air, their lives are largely a mystery. Fabre, the vener- able French naturalist, has made the most ex- tensive investigations on this period of the ci- cada's life, and he states that the insect feeds on the roots for about four years, undergoing several moults as it grows, until eventually, when it is ready to emerge, it selects a succulent
Ovipositor : View from Above.
root, and commences its last work of excavat- ing the straight tunnel to the surface. It uses the sap it obtains from the root, which is at the foot of the tunnel, to moisten the hard earth through which it has to burrow. When the tunnel is finished, it awaits an opportune time to make the great adventure — its transformation from a silent, grimy worker in the bowels of the earth to a light- winged, joyous creature of the sun. And if in the expression of his joy his screeching is distracting, we should remember, the years he worked before he gained his brief holiday, which, with the best of fortune, will last only a few days before his death.
A TRIUMPHANT DELIRIUM. 'Do not let us again reproach the adult in sect with his triumphant delirium,' says Fabre. 'For four years, in darkness, he has worn a dirty parchment overall ; for four years he
Side View of Ovipositor.
has mined the soil with his talons, and now the mud-stained sapper is suddenly clad in the finest raiment, and provided with wings to rival the birds. Moreover, he is drunken with heat and flooded with light, the supreme ter- restrial joy. His cymbals will never suffice to celebrate such felicity, so well earned, although so ephemeral.' Fabre's period of four years is estimated as a result of observance of the various moults. In America, however, it has been established that
one species lives 17 years underground. The exact period appears to vary for different spe- cies, and for different climates. When the cicada emerges from the ground, it crawls straight for the nearest tree, fence, or stick. It is in a great hurry now to get rid of its old and dirty clothes. It climbs up a few feet and plants its claws securely in a crevice. Presently the outer skin or shell splits down the back. The cicada carefully protrudes its head and shoulders, and slowly withdraws its feet ; it throws its body right back like a gym- nast in order to 'facilitate the apparently pain- ful operation. The wet wings, which have been curled against the body, hang limply down and slowly unfold, showing the delicate color of a soap bubble. The whole body is wet and soft, but soon hardens in the air. In the morn- ing, as the first shafts of the morning sun play around the trees, the cicada begins to realise that it has reached the day of its dreams. It climbs higher up the tree, tries its wings, and essays a short flight. Presently it discovers it
is hungry ; it searches about until it finds a suitable twig, buries its rostrum in the bark, chirps to its neighbors that all is well, and then shrieks its delight to a wider world. SPLENDID SPECIMENS AROUND SYDNEY. Many of the finest cicadas are to be found around Sydney. The first favorite with the small boy, whose collecting enthusiasm lasts only as long as the unfortunate insect can squeak, is the Double Drummer. This is a handsome brown insect with two sides of its thorax curiously distended. It has a strong
The 'Red Eye' (Half Natural Size).
sonorous tune when strumming to defeat its ri- vals in the attraction of the females, very dif- ferent from the sharp notes of protest it utters when captured either by a boy or a bird. It measures about five inches across the wings. Another fine cicada is the 'Green Monday' or 'Yellow Monday,' which has a voice just as loud as the 'Double Drummer,' though with
less tune in it. All cicadas have three simple eyes on top of their heads, in addition to the two large prominent compound eyes. The gem-like eyes set on the crown of the 'Green Monday' are ruby-red. Mr. Froggatt says this variety does not ap- pear to feed. It would be worth while noting its behaviour at different times of the day, and on different trees.; Some of our young obser- vant naturalists might have something to say on this point. The 'Red Eye,' a black cicada, is somewhat smaller than. the two previously mentioned, and, unlike the 'Green Monday,' is a voracious feeder. It is not able to consume all the sap it sucks out of the bark of the spotted gums and other smooth-barked trees, but sends some of it down in a fine spray. Very similar to the 'Red Eye' is the 'Fiddler,' another black cicada, which gets its name because of its thin, tuneful note. The distinctive appearance of
the 'Flowery Baker,' another favorite, is due to its covering of fine, soft hairs. The ''Squeaker' is the name given to the small cicadas which spend their time in the low scrub, and which are so elusive that one is inclined to credit them with ventriloquial powers. NOT A PEST. It is strange that, since cicadas are so large
and so numerous m Australia, they do not be come serious pests in the orchard as they are deprived of their natural food by the spread of settlement. Occasionally a few trees are in- jured by cicadas swarming in the branches and scratching the bark to lay their eggs, and last year some orchardists reported that a great number of their peach trees were badly dam- aged by 'Squeakers,' but, generally speaking, the damage done is very slight. The cicada's work can be done when it is in the larval stage, feeding on the roots. Any large number of ci- cadas continuously draining away at the roots of a tree would naturally weaken it, and render it less able to resist the attacks of other pests. The cicada, however, has many enemies, and although each female lays an average of about 300 eggs, very few indeed of these can ever reach maturity and develop the full life-cycle of the insect. Above ground the insects are attacked by birds and by wasps, and below
The 'Squeaker' (Natural Size.)
ground by fungoid diseases. The adult insect cannot even enjoy its meal without interruption, for hungry flies, beetles, and ants come to take advantage of the cicada's mechanical ability in boring a hole to the sap. The cicada is prac- tically without means of defence, and suffers the others to take advantage of its labor with out protest, until the bold, ungrateful ant, not content with the cicada's benevolence, will seek to pull its rostrum from the well.