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

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The second species, Pogonocerus hispidus, may be distinguished by the fact that it has two tubercles on the upper surface of the thorax, one spine on each side, and the tip of each elytron developed into two teeth, of which the outer is the longer. There are also some little black patches of hair near the tips, close by the suture. All these species have much the same habits, and can be found among dry wood.

The insect which is represented on Woodcut XXI. Fig. 5, inquisitor, and belongs to the family of the is called Rhagium Lepturidse. In this family the eyes are nearly rounded, and are of moderate length and set before the eyes. the antennae is bent rather downwards and narro\ved into a neck, The head is narrower in front than the head, and the elytra are the thorax from the base to the tips. In the genus gradually naiTOwed

Jlhagium the body is rather flattened, and there is a sharp

spine at either side of the thorax. The word Ehagium is a

Greek one, and signifies a little beriy.

Theie is not the least difliculty in distinguishing the present species. The colour is blackish, but the surface is covered with a very fine yellowish down, and is thickly punctated. The elytra have an elevated line, or rib, running longitudinally along them ; and upon the middle, or disc, there are two irregular reddish-yellow bands, placed as shown in the illustration. During its larval existence this insect lives in decaying ash and willow-trees, and may be dug out of them in spring, and found on and about them in summer.

There IS another species, not so common as the former which inhabits decaying fir-trees. Only a short time before writing this account, I dug several of them out of some firstumps near my house. In one small stump, not more than seven inches in diameter, I found four specimens. The name • of this species is Rhagium hifasdatum. It is marked much as IS the preceding insect, but may be known by a conspicuous groove along the top of the head, and the fact that the elytra have three longitudinal ridges instead of one. The bands, too, are shorter, and yellow the colour both of these and the

It is a remarkable fact that these insects invariably assume a perpendicular position before changing into the pi^pal form They may always be found mth their heads upward!, Ind their antennae and legs packed closely against their boches Their behaviour when the light is allowed to shine on Ih beT:;r„nr?htzx“^^ I

The nest, or cocoon, which the . Beetle makes S a va fcm 5 ItT' t prepares an oval mdergoes its change into the pu™l chamber, and within i-Eio i ^ v S';LTarsiTtT' in which -wch it it :Zg:: ^

great art, so as to form a soft bed ^»ng the long period of quiescence. It iZfe,:;:;^:

one of these nests, owing to the fragility of the material. One of them, in which a female Rhagium was reposing, was found in the fir-wood which has just been mentioned. The excavais rather more than an inch and a cj^uarter in depth, and the actual cocoon, which lies at the bottom of the burrow, is five-eighths of an inch long and not quite a quarter of an inch Avide. The mouth of the excavation, however, is an inch and in length, and a little ■ more than a quarter of an a quarter inch in width. I noticed that the inhabitant of this burrow, instead of availing herself of the opportunity of escape, as did crept closely into the recesses of the cocoon as all the others, opened, and would not leave it until she was soon as it was by force. The same stump contained two other removed hut none so perfect as that which has nests of the Rhagium, been described.

belonging to the same family, is shown on

Another Beetle, XXI. Fig. 2, and is known by tlie name of Strancjaha Woodcut this genus the thorax is without spines, is narrow in armata. In above. The body is very narrow and almost front and flattened The front of the head is rather lengthened. pointed behind. has the ends of the elytra deeply cut, so as The present species Avith toothed edges, and the male can to form a rounded notch tooth-like processes on the he recognised by two conspicuous hinder tibi®. Owing to these peculiarities, the inner side of the or ‘ armed,’ has been given to the specific name of armata, and size it is one of the most variable ot Beetle. In colour scarcely any two specimens being exactly alike. British Beetles, entirely black barred AVith yellovr, Sometimes it is almost with black, while it varies in length sometimes yellow barred of an inch. Being so variable, from five lines to three-quarters to have a series of specimens in his the entomologist ought There is not the least difiiculty in obtaining them, cabinet. and can be foun in p en y as it is a very common Beetle, these being the favourite upon the umbelHferous plants— resorts of many Beetles. It is tolerably active, ^ Seven species of this genus the Aving as soon as it is alarmed. are known in England.

CHAPTER XIII.

eufoba.

We now leave the Lengicorn Beetles, and come to another section, called the Edpoda, a name derived from two Greek words, signifying .beautiful feet.’ By some authors the section IS named Phytoplmga, this word being also of Greek oiigin, and signifying ‘plant-eater.’ They are all pretty insects and some of them, though not large, are singularly 0 this section the antenme are short and slender, and have a ti,/‘i^'*' deeply sunk into the thorax hut but one ouf of of T the tarsus ‘t has two j»“‘ lobes. They are all vegetablefeeders, and as most of them are attached to certain Ants theie IS little difficulty in finding ^ ’ them

Passing by the family of the SagrA, of which we have but fern species in England, With the Donaciad®. In all belonging to one thi<i genus^e be^ ^

fa fronAfTe *eyes“L‘ d a^s et jSt

Our exlmple o/thfa IS known to fam^Telongs‘t tteT“ T entomologists by the name of ttidis, a figure of which is'givL on wlc^^^

  • -ybe seen by

reedl! fe^rhiiTev'^" “ water-plants, especially on y reed. aOre^kTortt f;L aT^^^^ Although some of the species

are rather rare, the Donaciae are, beyond comparison, the most ■\vater“fre(^u.entin^ Beetles, and the leaves ot reeds, water-lilies, and other plants are often studded with these beautiful insects, whose polished and variously-coloured bodies glitter in the sunbeams like living gems. As many of the are exceedingly variable in colour, it will be as well for species

  1. Donacia MenyantMdis. 2. Crioceris merdigera. 3. Chrysomela Stapbylrea. 4. Cryptocephalus C017U. 6. Timai'cha lajvigato. a. Cbrysomela, antenna. 6. Cryptocephalus, antenua. c. Cryptooephaliis, labial palpi, d. Cryptocephalus, masiUary palpus, e. Donaoia, antenna. /. Crioceris, antenna.

number of specito procure a considerable the entomologist first sight appear to be different species, mens, many, which at seen to be nothing but vaneties being, when closely examined, is scarcely a colour of the rainbow of the same species. There by one or other of the Donaciie, and in which is not exhibited species exhibits an astonishing vai-ie(y some instances the same almost black, another blue. of colour-one being perhaps

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Illustration

another green, another copper, another purple, another red,

while another is as made of burnished gold.

The larvae of these Beetles live within the stems of the

various water-plants, and on that account the species have

derived their names from the plants on which they live. One

species, for example, takes its name from the bog-bean, or

yellow water-lily {Menyanthes nymphceoides), on which it is

found. Another is named Donacia typhce, from the common

bull-rush or reed-mace {Typhcb latifolia). Another has the

name of Donacia sagittarice, from the arrow-head {Sagittaria sagittifol%a') ; and so forth. Altogether, exclusive of varieties, of which there are a great number, nineteen British species of this beautiful genus are known. In some places these Beetles are so plentiful that seven species have been found on waterplants within the limits of one small pond.

The present species is shining-green above with a brassy gloss, and below it is silvery-white, owing to the soft down t I with which it is clothed. There is a bold groove on the front of the head, and the elytra are both striated and ‘ crenated,’ i.e. covered with little marks formed like segments of circles. It is not a very common species, being rather confined to certain localities.

The next insect on our list is that which is shown on Woodr! cut XXII. Fig. .2, and is known by the name of Gnoceris merdigera. It belongs to another family, the Crioceridae. In this family, the outlines of the eyes are notched, and the antennae are set in front, within the inner margin. The mandibles are short and abrupt at the tip, and have several sharp teeth. The genus Crioceris has the palpi slender, the joints of the antenme short, and the elytra wide. The name Crioceris is formed from two Greek words, signifying ‘ ram-horned,’ and is given to the insects on account of the form of the antennae.

Only three English species of this genus are known, of which the insect which is shown on the illustration is by far ; ; the most remarkable. Its colour is bright scarlet, but unfor- ^ tunately, as is the case with many brilliant insects, the colour V only exists during life, and fades rapidly after death. This ' lading IS generally caused by want of moisture, and in some . cases has been checked, if not altogether stopped, by opening

the insect, and introducing a small quantity of glycerine into the body and under the elytra. This plan might he tried on species, and certainly would do no harm even if it the present did not succeed. The insect is a very rare one, but may be taken in the flowers of lilies.

The larva of this species feeds on lily leaves, and is possessed of a habit which, though very remarkable, is found in other Beetles belonging to the Eupoda. The digestive apparatus is so formed, that the excrements, instead of being dropped, as is the case with most animals, are pushed upon the back, where they soon dry, and form a covering which larva equally against the sun and the rain. The protects the has the power of freeing itself at will from this very larva When full-fed, the larva descends to the singular covering. it burrows, and there makes an oval cocoon earth, into which in which it undergoes its changes.

known species of this genus is the Aspabagus

The best which feeds on the plant from Beetle (GHoceris asparagi), its name. This insect is much longer in the which it derives though smaller in point of body than the preceding species, prettily coloured, the thorax being deep-red, size. It is very elytra shining-blue or green-black, the latter and the head and so as to look as if they were being marked with reddish-yellow, cross had been laid. . The larvse are yellow on which a black and, together with the perfect grey, soft-bodied creatm'es, in any number upon the asparagus after it insect, can be found allowed to run to seed, and wave its feathery branches has been round fruit in the air. and pretty is represented by C^w

The family of the Cryptocephalidse on Woodcut XXII. Fig. 4 conjli, which is shown tocephalus is so deeply sunk in the thorax that it In this family, the head a pecuHarity which has earned is quite invisible from above, which signifies ‘ hidden-head. The for the insects their name, and black, the antenn® are slender, body is rather cylindrical The genus Cryptocephalus and the eyes are kidney-shaped. and as long as the body. One of has the antenn® slender, shown at Fig. b of the same illustration, the these antennaB is at c, and the maxilla palpus at d. labium

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