Cockroach (Malta, Linn.), an insect belonging to the order of orthoptera, and to the group of runners or cursoria, having straight wings, and all the legs adapted for rapid motion. The genus Matta has five articulations to the tarsi; the wings are folded lengthwise; the wing covers are oval, horizontal on the top of the back, and overlapping on their inner edges; the body is oval and flattened; the antenna) are long and thread-like; the legs have small spines. Cockroaches are general feeders, eating indiscriminately both animal and vegetable substances. They undergo only a partial metamorphosis, their changes consisting in the increase and development of the wings and their covers, which exist as mere rudiments in the nymph state; in other respects the nymph and larva are like the perfect insect, walking and feeding in the same manner. They are nocturnal insects, and live both in the woods and in houses. They run with considerable swiftness. There are several species; those indigenous to this country are found exclusively in woods, under stones and leaves, while the common species, originally from Asia, infests dwelling houses, preferring warm and dark closets, ovens, and hearths, whence they issue at night in search of food.

The oriental cockroach (blatta orientalis, Linn.) is spread extensively over Europe and America, especially in the maritime towns, being imported from the Levant in ships' cargoes. In many houses they are a perfect pest, devouring all kinds of animal and vegetable articles of food, and even destroying clothing, leather, cotton, and wool; on the approach of a light they escape with considerable rapidity into their holes. Eatables which they cannot devour are often rendered unlit for use by the disagreeable smell communicated to them by their excrements.

Cockroach. 1. Male. 2. Female.

Cockroach. 1. Male. 2. Female.

In old houses they swarm in great numbers, and the usual way to get rid of them is by poison. A mixture of red lead, Indian meal, and molasses, in a thick batter, placed at night near their haunts, will be eagerly eaten, and will soon exterminate them. Another more dangerous preparation is a mixture of a tea-spoonful of powdered arsenic with a table-spoonful of mashed potato, which may be crumbled about the hearth at bedtime; this requires great caution in its use. Phosphorus mixed in a paste will kill them, and they are often driven away by borax, to which they have a great antipathy. The females lay one or two oval capsular bodies about as thick as one half their body, each containing 16 eggs. The cockroach is terrestrial in all its states, and equally omnivorous and voracious in all.