All public Sources
Public document

Insects at Home: Being a Popular Account of British Insects, Their Structure, Habits, and Transformations

PDF document782 original pagesPublished 1 January 1876
AskTalkView media
Reading progressPage 38 of 117

overpowering, and in the next, the wood is filled with a

wonderful variety of animal life. In some burrows, close to

the bark, may be seen the glittering green bodies of newlydeveloped Beetles, as they lie waiting until their surfaces have j acquired sufficient hardness to enable them to face the dangers I of the world ; in others the helpless pupm may be seen ; and in

others, the white, flat, soft-bodied, hard-headed larvse move themselves restlessly as they perceive the unwonted light. The many burrows which have been evacuated by their makers are, ; however, seldom empty, but have plenty of tenants in the shape I of woodlice, centipedes, earwigs, spiders, millipedes, and sundry predacious Beetles, the latter having evidently burrows in search of food. entered the

Those who wish to capture the Musk Beetle will find that they cannot do better than explore the largest, the oldest, and the most rugged mllow-trees. The Musk Beetle is not a very j active insect, and is fond of clinging to the bark of the willow I and remaining perfectly still for many hours together. I may ; inention that the surface of this Beetle aflfords a most gorgeous I object for the microscope.

called cal? H ^ Galhd%um ^77 ^ beetle violaceum. In this genus the head is sunk in the thorax nearly as far as the eyes, which are semilunar. Ihe body is slender, and the legs short.

Tlje present species derives its specific name from its colour, w ,ch IS violet, sometimes glossed ivith green or tronze. Whatever may be the exact hue, a deep, rich, shining violet is always the predominant colour-a violet that woiUd make «.e fortune of any dyer if he could only transfer it to silk. little R ^“*1™ “™ely punctured. This pretty ht le B,*tle IS thought to have been introduced into this known that wood-boring BeeUe? Beetles are often transported from one country to arva or 0 2 another thf pupa remaining in the wood after the tree is cut down

and shaped into timber. Sometimes a Beetle has been known to emerge from a piece of furniture which has been in the house for several years, the changed conditions having retarded the growth of the Beetle, This insect inhabits the fir-tree, and, as it has of late years become comparatively plentiful from being one of our rarest Beetles, it is likely that many specimens are imported in the fir cargoes from Canada, where it is one of the commonest of insects.

The owners of the trees in question would be only too glad if the Beetle were less common, for it does very great damage to the timber, seizing upon the trees soon after they are felled, and laying its eggs in crevices of the bark. When the larvEB are hatched they set to work at their burrows, driving oblique tunnels deeply into the body of the tree, and so spoiling the timber. As is necessary for such a task, the larva is furnished with exceedingly stout and strong mandibles. Four British species of Callidium are known.

On Plate VI. Fig. 10, may be seen a figure of a very common

very pretty Beetle, belonging to the same family, and and known to entomologists by the name of Clytus anetis. In this genus the antenniE are shorter than the body, the last joint somewhat conical. The palpi are short, with the last being joint stout and three-sided, the angles being rounded. The thorax is globular, and the body is cylindrical.

The colour of this species is black, with three yellow bands the elytra, and a yellow patch at their tips, so that the across insect has a very waspish look, and is popularly known as the Wasp Beetle. The similitude is increased by its fussy mode and the perpetual movement of its antennae, and, of walking, as it crawls in and out of the foliage on hedges, it has so very wasp-like a look that few persons, except they be entomologists, to touch it. In its larval state it bm-rows into wood, and like midsummer. It is fond of freemerges somewhere about quenting flowers, and can be taken in almost any quantity. in the hue of its markings as well as in Being rather variable size, a series ought to be taken tor the cabinet. insects, it sometimes makes its ap-

Like many wood-boring pearance when it is least expected. In 18.33, for example, Mr. visitation of the Wasp Beetle in his

Denny described a emdous

museum. He had a case of stuffed birds, in which the birds

iiad been made to perch on oak branches. These branches had

been first carefully dried and then baked, and yet, after the

lapse of three years, three specimens of the Wasp Beetle

emerged from the branches, having survived the very unpleasant process to which they had been subjected.

This is not a solitary instance of the appearance of the Wasp Beetle. In 1865 a piece of pollard oak was sent to the British Museum, for the purpose of exhibiting the round, hard galls of Gynips Hgnicola, which was then not nearly so common as it is now. The oak, with its crop of galls, was placed in a glass case, together with a large lump of camphor, a material which is supposed to be poisonous to insects. Yet, on every succeeding spring, several specimens of the Wasp Beetle made their escape from the wood in which they had passed their larval state, the camphor having had no injurious effect upon them. A still more curious example of the unexpected appearance of a wood-boring Beetle will presently be mentioned.

Ode last example of this family is shown on Woodcut XXI. Fig. 1. Its name is Gracilia pygmcea. This genus is to be distmgmshed by the long slender body, the clubbed femora, the long fifth joint of the antennee, and the elongated last joint of the palpi.

As its specific name implies, this is a very small insect, never exceeding a quarter of an inch in length, and being generally much less. The colour of the Beetle is reddish-brown, with the exception of the under surface of the abdomen, which is shining-black. There is an angular projection in the the middle of

elytra.

This tiny wood-borer is one of those insects which are very local, but very plentiful in those places which they choose for their residence. Sometimes it prefers to live in houses, and soinetimes in the open air. It takes as great a range in point of diet as in residence. Its ordinary, and indeed its normal food IS decaying wood, and the insect may found in old railings and accordingly be’ similar localities. But it sometimes takes a strange fancy for leather, and has been captured in some numbers while feeding on old shoes. Sometimes snecimens of this insect have been taken in the middle of flour

barrels ; the larvae having probably been hatched in the wood of which the staves were made, and then relincjuished their original habitations for the richer diet furnished by the flour.

We now come to a most extraordinary insect, which is drawn on Woodcut XXI. Fig. 3. It goes by a great number of names. The scientific title by which it is now known is

pygmsea. 2. Straagalia armata. 3. Astinomus lediUs. 4. Pogonocerus pUosus.

  1. GracUia 8. Rhagium inquisitor. cedilis. There is no possibility of mistaking this Astinomus representative of its genus, which may be insect, our sole body, the tubercles on the sides of known by the broad flattened enormous length of the antenna3, which in the thorax, and the as long as the body, and in the males somethe females are twice times the length of the body. This times more than four is obtained by the elongation of the joints, inordinate length not by multiplying them.
<!-- pandi-media-anchor:figure-p248-o42-bfa748213c75d619 -->
Illustration

This is essentially a northern insect, being seldom seen alive

south of Scotland. Eannoch Wood is the best known locality

for this wonderful Beetle, and in that favoured spot the experienced entomologist will generally manage to capture it. Indeed, it is plentiful enough to have gained a popular name, that of Timbeuman, not only because it frequents timber, but because its long antennae present, when spread, a curious resemblance to a pair of compasses, these being used by the timbermen in calculating the cubic contents of a tree-trunk or log of wood. The specific name, cedilis, is that of the officer who in ancient times had charge of houses' and public buildings. When the insect flies, the long antennae trail behind it, and present a very curious appearance.

Unfortunately for the entomologist, the males are exceedingly quarrelsome, and when two of them meet together they are sure to fight, especially if one of the opposite sex be at hand. Their combats are so fierce that mutilation is sure to be the result to one or both, so that a perfectly complete specimen is of no small value for the cabinet.

In its larval state the Timberman Beetle lives in the interior of pine stumps, its tunnels being of considerable size. When it is full-fed, it makes a nest near the bark, in which it changes to the pupal state. The pupa of a male Timberman presents a very curious sight. All insects with long antennae have some remarkable mode of packing them away while they still retain the pupal form. In this Beetle they are brought down by the sides, along the body, and then curled back again over the head, so as to make two large loops, one on each side. The larva changes to the pupal form somewhere about the end of May, changes again to the perfect form in about a month, but does not leave its nest until the following summer, its surface gradually gaining consistence and hardness durino-’tfie time of its long repose. ^

It has been already mentioned that this is a northern insect. Only the day before writing this account I was in the British Museum, and asked whether the Timberman had ever been taken in any of the southern parts of England. The answer was, that the only southern place where it had been captured alive was the British Museum. The insect had been discovered ithin the walls of the Museum, having evidently escaped

from timber which was being iised for building purposes. This Beetle has also been discovered embedded in a seam of coal at Coatbridge, at a depth of nearly 900 feet from the level of the ground. It is evident that the insect must have emerged from some of the timber which is so largely employed in coalmines.

A RATHER remarkable Beetle is shown on Woodcut XXI. Fig. 4. Its name is Pogonocerus pilosus, both of which titles refer to the structure of the antennae. In this genus the body is short and rather convex, the disc of the thorax is covered with tubercles, the tips of the elytra are developed into spines, and the antenna are covered beneath with a clothing of hair. The generic title Pogonocerus (mostly, but wrongly, spelt Pogonoche'i'us) is formed from two Grreek words, the one signifying a beard and the other a horn ; so that the whole word may be translated as ‘ bearded-horn.’ The specific name, pilosus, is Latin, and signifies ‘hairy.’ There are three known English species, one, Pogonocerus fascicularis, being very rare, and the other two moderately plentiful. The present species has the tubercles of the thorax pointed, and there are two sharp spines on either side of the thorax. The general hue of the insect is reddish-brown, the elytra having a broad grey band at the base, and some black spots near the sutme. They have also a single spine on the outer edge.

Continue reading
Page 38 of 117