The various species of this genus deposit their eggs in the eggs of other insects, particularly those of moths and butterflies, and so very minute are some of them that a single butterfly’s egg will serve for the support of several Teleas’ larvae. By the assistance of these tiny parasites, it therefore happens that even the eggs of the Lepidoptera are destroyed before they can hatch, and so our gardens and crops are protected by friends so exceedingly minute that they can scarcely be aid ot a lens. seen without the

** “ Woodcut XXXII hig. 2. It JS called Myrnar pulchellus. lu this fh„T f while those of the female have only nine. The first joint is very and slender. The very long remarkable little insect which is Lawn hrisM lower pair of wings reduced to mere bristles, aud the upper pair are little more than two very long nervures with a broad fringe at the ends. This speciel maf be taken with the sweep-net by brushing it overgrass fhroughout crawling up the window-panes of houses, when they can tak^n by putting a pill-box over be easilv them. ^

The next group of this enormous array of Hymenoptera is that which is called Tubulifera, or Tube-bearers, because the last segments of the abdomen are modified into a telescopic and retractile tube. The antennae are elbowed. Only one family belongs to this group, namely, the Chrysididae, popularly

Chrysis :gnita, 2. Mutilla Europaea, female. 3. Mutilla Europaea, male. 4. Foimica mfa, winged female. 6. Do., neuter or worker. 6. Do., winged male. a. Formica rufa, labium. 6. Do., antenna^ male. c. Do., antenna, worker.

called Ruby-tailed flies, and familiarly known on account of their splendid colouring.

At first sight the abdomen appears to consist of a very few segments, sometimes three, and five at the utmost, but, in fact, the missing segments are modified into the telescopic tube which has just been mentioned, and which is retracted within the body when not required for its legitimate purpose, namely, the deposition of eggs. The abdomen is attached to the thorax

by a very short foot-stalk. In consequence of the mode by

which the abdomen is attached, the insect is able, when alarmed,

to roll itself up into a ball, in which it is aided by the shape of

the abdomen, the under surface of which is concave so as to

receive the thoraxr At the end of the retractile tube, is a

small, sting-like ovipositor, capable, as I can testify from experience, of inflicting a smart prick when the insect is moved

to anger. There is, however, no poison-gland, so that the prick,

though it may startle, cannot injure.

The Ruby-tailed flies are among the most beautiful of our insects, and if they were only enlarged, might challenge the most gorgeous productions of the tropics for brilliant splendour. The head and thorax are coloured with vivid blue or green, and the abdomen is of a fiery ruby, looking, as the insect flits about in the sunshine, as if made of burnished metal. Five genera of these insects are known to inhabit England, containing altogether about twenty-four species. They are all parasitic upon other insects, mostly afiecting the larvae of solitary Hymenoptera, among which the well-known Sand- wasp (^Odynerus) is so frequently the victim that Dr. Chapman, who has paid great attention to the Chrysididae, states that ‘ the destruction caused by Chrysididae amongst the young brood of Odynerus spinipes, roughly measured by the cocoons collected last winter, is in the proportion of one to three of those of the wasp.’ The mode in which these parasitic insects achieve their task is so well narrated by Dr. Chapman that I cannot do better than quote his own words.

On July 17th I observed a nest of Odynerus parietum, with one ^ cell open, and containing a nearly complete supply of Lepidopterous larvae. A Ghrysis ignita, flying about, settled beside the cell; and, after a brief examination with her antennae, wheeled round, and introducing her abdomen into the cell, rested for about twenty seconds, doubtless in the act of oviposition. I now regret that I did not then examine the contents of the cell, in order to ascertain the fate of the egg of Odynerus parietum. Three-quarters of an hour later Od/ynerus parietum had closed the cell with the usual earthen pellets. Two days afterwards I examined this cell, when I found a larva of Ghrysis ignita a quarter of an inch longtogether with the Lepidopterous larvae stored by the wasp, but

there was no trace of either egg or larva of the latter. On the 23rd, six days from the date of oviposition, the Chrysis larva had eaten all the store, and was full-fed. I obtained evidence, by finding the exuviae, of its having cast its skin three times, whilst under observation; and from the analogy of Chrysis hidentata, I believe it had done so four times altogether. The stored larvae had all been eaten, their heads alone remaining, just as when eaten by the wasp grub. The larva then spun a cocoon, which I know to be typical of G. ignita. This was the only occasion on which I had a feeding larva of G. ignita, and the rapidity with which it fed up astonished me. None of my G. neglecta or hidentata fed up so rapidly; but the warm sunny wall on which 0. jparietum had built her nest may partly account for this, my larvae of the other two species having been kept comparatively cool.

‘ Chrysis hidentata, about to deposit her eggs, searches for a full-grown larva of Odynerus spinipes at, or immediately after, the period of spinning. 0. spinipes, on the completion of her burrow, fills up the mouth with clay long before the most accessible cells can contain full-grown larvae ; but it happens that, in a large proportion of cases (^about half), the wasp meets with some accident, and her burrow remains uncompleted, the cell last constructed being thus only protected by the wall of clay that was to serve as a party wall between it and the succeeding one, had the wasp lived to complete her Such slightly protected cells are those choseu by work. G. hidentata for her oviposition. I once found satisfactory evidence of G. hidentata burrowed through half an of the clay stopping placed by the wasp over one of these inch cells. The parasite was in the burrow, covered with the dust down into it by her excavation to form an entrance — brought a passage too small for the wasp to enter, but just large for herself ; and in the cell thus reached by her were to enough eggs, freshly deposited. On another occasion, a be seen her alighted on a spot I was examining, and where I C. hidentata some cocoons of 0. spinipes : she comhad partially exposed investigate them with her antennae, and menced to carefully now and then to scratch away some earth partly covering them ; she did not, however, deposit any egg, possibly because the inmates of the cocoons were not in proper condition.

• ‘When a cocoon contains eggs of G. hidentata, there is often to be found, at its upper end, a minute aperture, through which the ovipositor of the Chrysis has been thrust ; at other times, this aperture is wanting, simply, I believe, because the: larva of 0. spinipes had not done spinning her cocoon when the Chrysis deposited her eggs within it. There is nearly always a small spot outside on the yellow silken top of the cocoon, as if the Chrysis had attacked it first with her jaws ; and those containing C. hidentata may be selected by this mark from a number of cocoons of the Odynerus.

‘ The young larva of G. hidentata seizes that of 0. spinipes with its jaws, pinching up a fold of skin, and contrives to extract fluid nutriment from it, without, apparently, making any aperture in the skin, until it approaches to mature growth itself. I have very carefully examined larvae of 0. spinipes that were thus half sucked away (I cannot say eaten), and I could find no mark at the spot whence I had just removed a larva of Chrysis. I have several times squeezed the Odynerus larva firmly, without any fluid exuding : even when squeezed almost to bm-sting, on only one occasion did a drop of clear fluid exude. Nor is the Chrysis larva particular as to where it seizes the Odynerus, any point that may offer itself to its jaws being seized.

‘ When the devourer is nearly full-grown, and the victim is very flaccid, a process that may be called eating takes place, and the spinipes larva almost entirely disappears. The manner in which the larvae of G. neglecta and ignita and of 0. spinipes itself eat the little green grubs is precisely similar. When young, they merely suck the juices of several, and sometimes return to and finish these when they are larger, but they may often be found neglected when the larva is full-grown.’

These insects are wonderfully persevering in their attempts to deposit their eggs. A French naturalist mentions that he saw one of them enter tbe nest of a solitary bee which builds in the holes of walls, while the bee was absent in search of the pollen on which the young larva was to feed. She happened to return while the Euby-tail was still in the nest, and at once attacked the intruder, which endeavoured to avoid her jaws by rolling into a ball, after the fashion of her kind. The bee however, persevered in her attacks, bit off all the enemy’s wings’

dragged lier out of the nest, threw her to the ground, and proceeded to deposit her load of pollen in the cell. She then flew off in search of a further supply, when the Kuby-tail, all mangled as she was, crawled up the wall, re-entered the nest, and succeeded in depositing her egg, which she pushed carefully between the pollen and the wall of the cell, so that tlxe hee should not see it on her return.

CHAPTER III.

Ants And Diggers.

The insects which compose the remainder of the Hymenoptera have been arranged by Mr. F. Smith, who has brought to bear upon them an enormous amount of labour and knowledge. His arrangement and definitions will be observed in this work. He divides them primarily into four tribes, the first of which is called Heteeogyna. These insects are sometimes solitary and sometimes social, the latter being more common than the former. The social species have apparently three, but really only two sexes, namely, perfect males, perfect females, and workers, which are, in fact, partially developed females. The males are always winged, but the females only possess these organs temporarily. As to the solitary species, the females are altogether without wings.

The first division of the tribe is the Aculeata, or stingbearers. In them, the females have an abdomen consisting of six segments, and furnished with a sting. The antennae have twelve joints. The antennae of the males have thirteen joints, and the abdomen has seven segments, but has no sting. In fact, as the sting is a modification of the ovipositor, it follows that no male insect can possess a sting.

We pass to the first family of these insects, the Formicidae or Social Ants. In this family the head is more or less triangular, and the basal joint of the antennas is extremely lonooften occupying half the length of the entire organ, and forming a bold elbow at the juncture with the third joint. The eyes are placed at the sides of the head, and do not reach to its top. In the perfect males the ocelli are three in number set triangularly, and larger than those of the opposite sex. The wings are large and delicate, and only exist in the males and

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