PLATE XLIX.

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LOCUSTA (RUTIDODERES) SQUARROSA.

Plate XLIX. fig. 1.

Order: Orthoptera. Section: Saltatoria. Family: LocustidÆ (Acridites, Serv.).

Genus. Locusta. Gryllus; Sect. Locusta, Linn. Gryllus, Fabr. Acrydium, Latr. (Subgenus. Rutidoderes, Westw. Acrydium, Serv. )

Locusta (Rutidoderes) Squarrosa. Viridis, pronoto tripartito spinoso, elytris viridibus fusco-punctatis, alis rubris nigro punctatis. (Expans. Alar. 4 unc.)

Syn. Gryllus Squarrosus, Linn. Mant. 533. Fabr. Ent. Syst. 2. 52.

Habitat: Sierra Leone.

Head green. Eyes perfectly round and dark brown, very prominent, and standing at a little distance from each other. AntennÆ 18-jointed, longer than the thorax, which is dark green, and on the upper part gibbous; having on each side three swellings, each of which terminates in three short and thick spines. Tegmina darkish green, with a great number of small black spots on them of different shapes. Wings scarlet, spotted with black; the spots being larger than those of the wing-cases, and of different shapes. Abdomen green, with several yellow rings surrounding it, and about the same length as the tegmina. Legs green; the thighs being armed with spines.

Our author states, that he was informed by a gentleman who lived several years at Sierra Leone, and by whom this species was communicated to him, that "they appear about the end of June, and soon afterwards retire among the branches of the palm trees, where they reside till the violent rains compel them to quit that situation, and live among the plants, &c. on the ground." In the Introduction to the third volume, he however states on the authority of Mr. Smeathman, that "this beautiful locust is an inhabitant of the sandy plains, called Savannas, which indeed abound with palms; but my friend is in doubt whether they have any kind of predilection for those trees.

"'Although the hot climates abound in every part with insects of the locust and cicada kinds, insomuch that their chirping, particularly that of the cicadas, becomes in some instances intolerable; yet in the sandy plains before mentioned, which are thinly covered with grass, their numbers are immensely greater, and of various kinds, sizes, and colours, skipping or flirting about in all directions at every step of the traveller.' Perhaps, indeed, their kinds may not be so various as one would at first imagine, the same insect differing so much from itself in the various periods of its life. From the fact however here mentioned, it seems most certain that these insects breed under ground in Africa, as well as in these climates, according to LinnÆus and other entomologists."

From the knowledge which we possess at the present time relative to the economy of this tribe of insects, it is necessary to observe, upon the last above-quoted passage, that the term "breeding under ground," must be restricted to the mere circumstance of the eggs being buried beneath the surface of the earth, because the insects in all their active stages (including that of the pupa) feed upon grass and other vegetable substances above ground.

In following up the very proper plan proposed and partially effected by Mr. Kirby, in the Zoological Journal, of restoring to the primary divisions of the LinnÆan genus Gryllus the names which he gave to them, and which have been so confusedly employed by Fabricius and the French entomologists, and of which I have elsewhere given a more complete explanation, it is necessary that the generic name Locusta should be restored to the true migratory locusts composing the genus Acrydium of Latreille, and that a new name (Rutidoderes) should be given to the subgenus Acrydium of Serville, comprising the present and other allied species.

LOCUSTA TARTARICA?

Plate XLIX. fig. 2.

Order: Orthoptera. Section: Saltatoria. Family: LocustidÆ (Acridites, Serv.)

Genus. Locusta. Gryllus; Sect. Locusta, Linn. Gryllus, Fabr. Acrydium, Latr. (Subgenus: Locusta. Œdipoda, Serville.)

Locusta Tartarica. Thorace subcarinato tripartito; fusco, line dorsali pallidÂ; elytris fulvescentibus fusco punctatis, alis hyalino subvirescentibus. (Expans. Alar. 4 unc. 6 lin.)

Syn. Gryllus tartaricus? Linn. Syst. Nat. 1. 2. p. 700. 42. Fabr. Ent. Syst. 2. 53. Serville Revis. Orthopt. p. 92. (Acryd. t.)

Gryllus americanus, Drury, App. vol. 2.

Habitat: Virginia, Antigua, New York, Madras, and Sierra Leone (Drury). "Tartaria et Africa." (Linn.)

Head striped with dark and light brown. Eyes oblong. Thorax dark brown; having a light brown stripe running along it from the front of the head, which, when the wings are closed, is continued along the margin of the tegmina; on the sides it is light brown, and margined beneath with stripes and spots of dark buff. AntennÆ thread-like, and about the length of the thorax. Tegmina dark buff-coloured, almost transparent, variegated with stripes and spots of different shapes; those next the shoulders being nearly black, and those toward the extremity more transparent. Wings very thin, and more transparent than the tegmina, being of a greenish hue. Abdomen light brown on the sides; having a small stripe of a paler colour running along it, and on the upper ridge is black. Legs pale brown. Hinder thighs almost square, the outer sides being white and prettily chequered, which, when viewed by a magnifier, seem like scales laid over one another; on the outside of the tibiÆ is a round white spot, and over that a long black one. Posterior tibiÆ brownish red, with two rows of spines on the hinder sides of a white colour, and tipped with black, consisting of nine in the outer and eleven in the inner row.

The different habitats given of this insect by Drury, leads to believe that he had confounded several closely allied species under one name, Americanus; which I should have adopted, but for its inapplicability for the individuals of the Old World. It is also on the like account that I have given the reference to LinnÆus with doubt, although Fabricius cites Drury's figure under Gryllus tartaricus without any hesitation.

                                                                                                                                                                                                                                                                                                           

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