To me, one most interesting point was to observe the economy of Nature even in so small an insect as a Grall-fly. Normally it has to bite its way through half an inch of material, and it has strength for that purpose. But it has not more than sufficient strength, and so it happened that the insect in question, after traversing its allotted half inch, had no strength to proceed further, and so died on the scene of its uncompleted ^ labours.

An insect so plentiful, so conspicuous, and so sluggish might be supposed to suffer much from birds. It has, however, been well observed that this species has, when handled a very^ disa^eeable odour, and that therefore the birds may reject it, as is known to be the case with many other insects.

It is impossible, with the limited space at our command, to do more than give this brief sketch of the life of a Grall-fly There are very many other species, some of which are exceedmgly beautiful and others comparatively dull. Breeding them fmm the gall is a very interesting pursuit, but I must warn t e novice in this art that, although he may hatch a number of Hymenoptera from galls, it does not by any means follow

lawful inhabitants ; for there are certain that they are its flies (of which we shall presently treat) which are iclineumon the gall insects, and take their place within the parasitic upon galls. produced by these insects are very

Some of the habitations the leaf-galls of the oak are of a beautiful. For example, and coloured with golden yellow, orange, pearly translucency, apple. The currant galls, which hang in and red, like a ripe from the twigs, are similarly beautiful in colouring, strings bedeguar of the rose, with its thick, while the rich crimson clothing, is too familiar to need description. fur-like which inhabit these galls is easy

To secure the insects are found at the middle or end of enough. Those which with the part of the tree autumn may be plucked, together and placed in boxes, each box to which they are attached, with the date and locality of the being carefully labelled the galls are found at the beginning of capture. But when because the galls are still drawsummer, this plan often fails, and, unless they can do so, the

ing nourishment from the sap, nutriment, and either perishes insect does not obtain sufficient through the partly dried walls of before it can make its way shrivelled, or deformed, in its habitation, or is itself withered, deterioration of its food. consequence of the best plan is to take a piece of green

In such cases, the over the gall. In gardens or muslin or leno, and tie it loosely the best plan, and, even in grounds this is always private the green muslin will mostly escape places open to the public, it is often so difficult to discover, that observation. Indeed, is to note in the pocket-book the particular the safest plan any galls have been thus seemed. tree and branch on which the G-all-flies can gnaw the It is rather cmious that, although habitations, they seldom, the walls of their former wav through the gauze in a similar manner if Iver, try to break through way, as if bewildered wi crawl about in an uncertain but their new position.

family of these msects,

ThuM! is one small but remarkable relation, size, and posit on the Evaniid®, in winch the

called and thorax are most curiously

of the abdomen now inhabiting Britain, they other groups of insects

several

are thought by many entomologists not to be indigenous, but to have been brought over by vessels, and to have acclimatised themselves.

In these insects the thorax is enormously large, and the abdomen is curiously small, scarcely larger, in fact, than one of the hind-legs. It is very slender, and attached to the upper part of the thorax by a slight footstalk, just below the insertion of the wings. In some species, the abdomen is barely half the size of one of the hind legs, and bears about the same relative proportion to the thorax that a comma (such as this

ears to the capital letter 0. In fact, the creatnrp SAPTna fr)

— la nuu yei tnoroughly known.

CHAPTER II.

The Ichneumon Flies.

We now come to the Ichneumonidae, one of the largest, most important, and most perplexing groups in the insect world. They are termed Ichneumonidae, or Ichneumon-flies — because they enact the same part towards various insects that the ichneumon was said to act towards the crocodile. They are parasites upon other insects, and for the most part they spend their larval existence within the bodies of their victims, where they lurk unseen and unsuspected until the time comes when they have to change their forms. In this family the abdomen is attached to the end of the thorax, and not to its upper part, as in the Evaniidse, and the first pair of wings have always ‘ perfect ’ cells, i.e. cells closed on all sides within their disc. The ovipositor of the females is straight, and the antennae are not elbowed. There are many other characters of this family, but these are sufficient for identification.

The first and typical genus of this family is Ichneumon, in which the abdomen is rather egg-shaped but oblong, and the ovipositor is not external. The antennae are linear, and the wings have the areolet five-sided and boldly marked. The outer cell is complete.

Our first example of this genus is given on Woodcut XXXI. Fig, 1, and is called Ichneumon 'proteus. Why it should have obtained the name of Proteus is more than I can understand. The name decidedly implies that it is exceedingly variable in some way, but in a long series that I have examined I could worth noticing. The colour of this not find any variation insect is black, with a yellow scutellum, and a yellowish patch in the middle of the antennae. The wings are translucent, but shaded toward the tips.

At Fig. 2 of the same Woodcut is shown the male of another

species of • this genus, Ichneumon crassorius. In this insect there is a bold distinction between the two sexes, the females being altogether black, with the exception of a yellow scutellum, and the males having a broad band of orange-yellow across the middle of the abdomen. When a female of any large species of Ichneumon is caught in the hands, she uses her ovipositor as a weapon of offence, by bringing its sharp point against the skin. She cannot do any injury, for she has no

Ichneumon proteus. 2. Ichneumon crassorius. 3. Trj-phon rutilator 4 rrvr>(-n«

of abdomen. c. Do., dned specimen. rf. Do., seen from beneath. c. Do., abdomen of poison apparatus, and the ovipositor is too feeble even to penetrate the skin. She can, however, prick sharply enough to cause a novice to think release that she really has a sting, and to her accordingly.

We now come to the genus Tryphon, in which the tarsi of

the hinder legs are very slender, the abdomen has a very short footstalk, and the areolet is not well defined, but is either triangular, or approaching to a circular form. One of these insects, Tryphon rutilator, is drawn on Woodcut XXXI. Fig. 3,

The present species is exceedingly variable, but in general the head and thorax are black, and the abdomen dull red in the middle, with a black base and tip. A rather curious circumstance has occasionally happened to one or two species of this genus. The eggs had been extruded — probably by pressure when the insect was caught — and remained at the end of the abdomen, where they were hatched. Having no proper food, they commenced feeding on each other. One of the larvse is shown at Fig. a.

On Plate X. Fig. 3, is seen a very fine Ichneumon-fly, which is called Trogns atropos. In this genus the scutellum is elevated, the head is large and wide, the abdomen is joined to the thorax by a footstalk, is convex, and the ovipositor is not protruded. The colour of this species is black, with the scutellum and the basal half of the abdomen yellow.

This insect preys upon the caterpillar of the Death’s Head Moth {Acherontia atropos), one of which is partly shown in the middle of the Plate. Those who rear moths from the caterpillar are too familiarly acquainted with the Ichneumon, for it often happens that, after watching and cherishing a caterpillar until it is full-fed, the creature dies, and from its withering body proceeds the splendid but objectionable Ichneumon. It is in consequence of choosing this caterpillar that the name of Atropos has been given to the insect.

Another species of Ichneumon is shown on Woodcut XXXI. Fig. 4, and is called Cryptus migrator. In this genus the ovipositor is rather long and protruded. In other respects it agrees with the preceding genus. This is rather a variable species, but in general it is black, with the exception of the abdomen, which is dark-red. It is parasitic on solitary bees, belonging for the most part to the genus Odynerus. The name Cryptus, which signifies hidden, was given to the insects on account of the manner in which they lie hidden in the bodies of their prey until they are developed. This is a very large genus, containing some sixty species.

On Plate X. Figs. 2, 3, and 6, are drawn two species of a most curious little Iclineumon, which might easily he thought not to be a winged creature at all. In this genus the abdomen has a footstalk, and the ovipositor is short and protruded. The wings are unfitted for flight. The generic name of Pezomachus is G-reek, and signifies a foot-soldier. It is given to those insects because the females are unable to use their rudimentary wings.

At Figure 6 is represented the female of Pezomaclius zonatus. The head of this species is black, and the rest of the body is yellow, with the exception of two black belts across the abdomen, from which the insect derives its name of zonatus, or belted.

In Pezomachus fcisciatus, which is seen at Fig. 3, the female is entirely without wings. Its colour is yellow, and it has a single black band on the abdomen, from which it derives its specific name of fasciatus, or banded. In one species, Pezomachus hemipterus, the female has very short wings with black tips. They are, however, merely rudimentary, and quite incapable of flight. The specific name of hemipterus, or halfwinged, refers to this structure.

The Pezomachi are parasitic on spiders, and can be almost always obtained by using the sweep-net among grass and bushes where the spiders nests abound. There is a very common spider, called Agelena hrunnea, which makes its nest on furze and grass, and then covers it with earth, so as to hide the white, glittering silk of the nest itself. From these nests the Pezomachus may often be hatched. In all cases, the male is much rarer than the female, and the surest mode of procuring it is to take a number of spiders’ nests and await the exit of any them. Pezomachi that may happen to have been parasitic on

One of the larger species of Ichneumons is represented on Woodcut XXXI. Fig. 5. Its name is Pimpla instigator. In this genus the abdomen has no footstalk, and is smooth and convex, with the segments marked by tubercles. The areolet IS triangular, and the ovipositor is protruded.

The colour of this species is black, and the legs are reddish. It IS a wonderfully variable insect in point of size ; some speci-

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