CHRYSOME'LID.E, a family of Coleopterous Insects of the section Cyclica. Characters :—Antennm wide apart at the base, and inserted before the eyes ; body generally abort and convex ; tarsi short and rather broad, 4-jointed, the penultimate joint bilobed ; all the joints, excepting the terminal joint, covered beneath with a velvet like substance.
The Chrysomelides constitute a very numerous and beautiful family of the Beetle Tribe : they are generally of moderate size, and fre quently very brilliant in colouring.
Between seventy and eighty species have been discovered in England, and the number of species contained in collections from various parts of the world may probably amount to four or five hundred.
This group may be divided into two sections : those in which the head is bidden beneath the thorax, and the body is frequently some what cylindrical ; and those in which the head projects from the thorax' so as to be distinctly seen when the insect is viewed from above, and where the body is generally rounded, or oval, and convex.
The first of these sections may again be readily subdivided accord ing to the proportions of the antennm. In some the antennas are short, and more or less serrated ; here belong the genera Clythra, Lamprosoma, and Chlamys. The species of this last genus are among the most remarkable of Colcopterous Insects. They are of small size, the largest being about half an inch in length, and the thorax and elytra are generally very uneven, and studded with numerous angular projections. This circumstance, together with the extremely brilliant colouring with which they are adorned, has caused them to be com pared to pieces of minerals ; indeed, one which is now before us, and which is of a beautiful red hue, we have known to be mistaken at first sight for a piece of copper-ore. Most of the species of Chlamys inhabit Brazil, and none are -found out of the western hemisphere. The generic characters are :—Head vertical; thorax humped ; the posterior margin produced in the region of the seutellum • body some what cube-formal ; with the basal joint rather long, the second very small • the remaining joints dilated,• and more or less serrated; labial sometimes forked.
The remainder of the Chrysomelicks of the first section have the antennae long and slender. The genera are Cryptoceph.alua, Choragua,
Euryope, and Eumolpua.
The second section, or those in which tho head is apparent when the insect is viewed from above, comprises the genera Colaspis, Podon tie, Phyllocharis, Deryphora, Cyrionua, Paropsia, Apanusa, Timarcha, Chrysomela, Phesdon, and Prasocuris.
The genus to which the name Chryaomela is now restricted, is principally distinguished by the following characters :—Maxillary palpi with the terminal joint as large or larger than the preceding one, and of the form of a truncated cone, or nearly oval ; the elytra are separate, that is, not joined at the suture ; no sternal projection.
Upwards of forty species of this genus have been discovered in England.
C. Banksii is one of the largest species of the genus : it is rather less than half an inch in length, and of a brown colour with a metallic lustre ; the thorax has an indentation running parallel with and close to the lateral margins ; the elytra are coarsely punctured ; the legs and antennm are ochre-coloured. It is found on nettles in the neigh bourhood of London and elsewhere, but is rather local. C. sanguine lenta is about three-eighths of an inch in length, and of a dull blue black colour ; the elytra are rather rough. C. Graminis is about the same size as the last, and of a bright-green colour; this species is abundant in various parts of Cambridgeshire. C. polite is about a quarter of an inch in length, and very glossy ; the head, thorax, and legs are green, and the elytra are of a reddish-ochre colour. This species is very common in marshy situations. C. cerealis is about the same size as C. sanguine/ea/a. This is one of the most beautiful spe cies of the genus. It is tolerably common in France and Germany, but till found on the summit of Snowdon (about twenty years ago), was scarcely known as a British insect. It is very glossy ; the legs, antennm, and under parts are blue ; the elytra are adorned with longitudinal stripes of blue, green, and red ; and the same colours are observed on the head and thorax. C. Goettingenais is of a purple colour, and the elytra are very finely punctured. This species is very common in chalk districts. [Cretres..)