Reference has been made to the too familiar hum of the ^ Gnat. This sharp and almost trumpet-like sound has been i carefully investigated, and by means of an instrument known as ; the Siren it is possible to count the number of beats made in a j given time by the wings of the^ Gnat. The Siren is an / instrument which can produce any required number of vibra- * tions, and as they are produced registers them on a dial. Now it is found that when the vibrations exceed a certain number ; per second, a definite musical sound is produced, the sound or ■ tone becoming sharper in exact proportion as the number of vibrations becomes greater. So, if a Gnat be heard to hum, ' and a Siren be forced to produce the same note, the instrument ; not only gives the exact note, but registers on its dial the number of vibrations required to produce that note in other words, the number of vibrations of the Gnat’s wing per second.

Here it roust be mentioned that these wings are moved in a very curious manner. It was formerly thought that they passed into the cavity of the thorax, and were worked by means of the powerful muscles attached to their bases. Such, however, is not the case. Let any reader take a fly — one of the many Hoverer flies is perhaps the best — kill it, and press the point of a pin lightly on the middle of the thorax. It will be found that as soon as the point of the pin presses the thorax, down go both the wings, so that in fact the movements of flight are made by the action of the thorax to which the wings are attached, and not by the action of muscles directly connected with the wing. In point of fact the wing moves by the rapid contraction and expansion of the mesothorax, such movement being caused by the powerful set of muscles within it.

There is much more to be said about the Grnat, but our rapidly diminishing space warns us to proceed to another typical insect.

On Woodcut LXX. Fig. 1, is represented one of our finest British examples of the insects called by the popular name of Daddy-long-legs, or Crane-fly.

The name of this particular species is Tijpula longicornis, the latter name being given to it on account of the great length of its antennae.

In the family of Tipulidse, to which this insect belongs, the proboscis is very short, with its internal organs very slightly developed. The legs are very long and slender, as is the body, and the alulets are almost wholly wanting. The larvae of some of the Tipulidae live in the water. Those of the genus Chironomus are long, slender, scarlet, and worm-like, and are wellknown under the name of Blood-worms. The rain-water butt is a favourite nursery of these insects, and their larvae may often be seen in the ewer, jerking and twisting about like little bits of scarlet thread endowed with life.

The general colour of the present species is ochreous-yellow. I he thorax is black, with a slight ashen- grey down, and there is a yellow semi-lunar spot before each of the wings. The abdomen has a short slate-coloured streak down each side. It IS a tolerably common insect, and can be seen while flyinoalong hedge-rows in the dusk.

The life history of all the members of the genus Tipula is very similar. The eggs are laid in the ground by means of the sharp ovipositor which is seen at tlie end of the abdomen of the female, and, when she is seen in the act of depositing her eggs, the object of the long legs is evident. She always chooses some grassy spot, and then stands almost erect on her hind legs

c. Larva. tl. Front view of mouth, showing the two lobes. b. rnpa.i

among the blades of grass, with the point of the ovipositor on the surface of the ground. She then begins to turn her body from side to side, just as the carpenter turns a bradawl when he wishes to bore a hole in a plank, and in a short time is enabled to deposit an egg beneath the surface of the ground. This done, she goes to another spot and repeats the process, until she has deposited all her eggs.

When the young larva3 are hatched, they make their way

among the roots of the grasses, on which they feed. One of these larvae is shown at Fig. c. They are tough-skinned, hardheaded beings, and do incalculable damage to our lawns and pasture lands, sometimes cutting away the roots of the grass so completely that large masses of turf are completely separated from the soil, and can be rolled up by the hand as if a tmTciitter had been under them. There is no remedy against these grubs which is half so effective as the starling. This bird has a wonderful power of detecting the presence of the subterranean larva.

If any of my readers will get up very early, so as to be abroad at day-break, and will hide himself in some convenient nook near a grass lawn, he will see how the starlings can work for the benefit of man. They evidently employ the sense of hearing as their principal mode of discovering their prey, and may be seen with the side of their beads pressed against the ground, evidently listening for the unseen grub. When they have made up their minds, there is no delay, for the bird gives half a dozen sharp pecks, thrusts its beak deeply into the ground, gives a strong pull, and hauls out the Tipula larva, which it has seized by the head. It does not eat the grub, but flies off with it, still holding it by the head with the very tip of its beak.

The pupal form of this insect is shown at Fig. h. When the pupa is about to change into the perfect form, the pupa issues partly out of the ground, and the skin then splits and allows the perfect insect to escape.

For the following interesting details of the Daddy Longlegs, I am indebted to the Eev. J. W. Brooks, Great Ponton Eectory, near Grantham : —

‘ Some years since, when I was Vicar of Nottingham, I turfed over a small plot in the garden at the back of my house with turves procured from a sandy meadow in the neighbourhood. They proved to be full of the eggs of the Fly above named ; and in the spring the grass portion of the garden, comprehending only about three hundred and fifty square yards was swarming with their grubs, with which I bad not previously been acquainted. They were sluggish-looking larvse curled, and apparently harmless. It was not until the period of their escape that I K R discovered what they really were, and

killed about twelve luindrecl by liand-picking, giving them a i squeeze in the head as they were taken.

‘ I did not, however, at that time understand tlieir habits, or the slaughter would have been greater. It was not until the latter part of the year that I noticed tliat the Fly comes forth from the earth at twiliglit— chiefly in the evening, but in tlie morning twilight also. They may then be easily taken by pacing about upon the grass, and watching them as they emerge. To aid their capture the grass should be kept close cut during the season of their appearance. I killed upwards of two thousand in the second year, and in the fifth year of their invasion, I saw no more of them.

‘ I observed that the male commonly leaves his case in the earth, and begins to fly immediately on his emerging therefrom ; or, after the lapse of a minute or so, while he rests upon the grass. He is small and active, and scuttles about close to the ground in a zigzag manner, like a spaniel in search of game. ,, ^

‘ The’ female, being fat and plump, particularly towards the • end of the abdomen, often cannot extricate herself from the 5 old case in which she has been entombed, as the abdomen | sticks fast in the upper part of it, which is the narrowest. I « have seen them shoot up by the half-score together in the twilight of a soft summer’s evening, unable to bring the case ^1 fully out of the ground. The wings at their extremities |1 encased together with the abdomen, and frequently remain thus the insect is prevented from struggling except with its fore-legs. jn

‘ I have measured them when in this position, and found W. attached, two inches and a half in length. 9 them, with the case are of a light blanched colour on their first coming 8 Both sexes forth from the ground ; but a few minutes with the female, and |L with the male, change them to their usual dustya few seconds drab. active, searching motion of the male t

‘ The reason of the he is hunting for the female. As x quickly becomes apparent— as he discovers one of them in the hampered positron soon he rushes to her aid, and with Ins fore-legs already described, light pupa-case. The insects remain

drags her out of the hours, and may thus be destroyed before

together for several the female has had time to deposit hci eggs.

‘ If the morning's or evenings are frosty or damp, tlie insects

are dull and torpid, and may easily be taken with the hand ;

but if the weather be hot and dry, they are lively and saucy,

and fly away as the cajitor approaches. They are, however, so silly, that often, when they seem to be flying away, they rise

up in the air, make a short gyration, and descend, with a sudden dart, at his very feet.

‘ The time of the appearance of the perfect fly varies according as the season has been warm and dry or cold and damp. In the course of the four years that I watched for them, their first appearance varied from the eighth of August to the fifth of September, and their disappearance from the fifth to the thirtieth of September. The jDrocess of transformation from the larva, to the fly continued, in the entire community of them, from twenty-one to twenty-five

days.’

The pupa of this insect is shown at Fig. h. Fig. a represents a magnified profile view of the head of the perfect insect, and hig. cl is the front view of the mouth.

We now come to the second division of the Cephalota, namely the 'Brachocera, or Short-horned Diptera. They are divided into smaller groups, or Stirpes, as Mr. Westwood calls them. The first of them is the ISTotacantha, or Thornbacks, in which the antennas are apparently composed of only three joints (of which the last is seen, when examined by a I lens, to be articulated), and the proboscis seldom contains I more than two lancets. The pupa is enclosed in the skin of the larva, which, however, retains its previous shape instead of being formed into an oval cocoon, as is the case with the common flies and bluebottles. We can only take one example of this group, the Forked Chameleon Fly {Stratiomys furcata), which is represented on Woodcut LXXI. Fig. 3. In this genus the proboscis is very short, and the basal joint of the antennae is much longer than the second. The third joint is I apparently very long, but the microscope shows that it is ^ composed of several joints fused together, as may be seen by i reference to Fig. h. ^ Most of the insects belonging to this family are beautifully ^ coloured, and many of them n shine u 2 with metallic tints, mostly

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