Blatta

Blatta, or Periplaneta, the cockroach, an insect belonging to the order Orthoptera, so that it is not a true beetle, though popularly known as the "black beetle." The body is invested in a hard brown coat or cuticle; it is divided into a number of distinct segments grouped into three divisions, head, thorax, and abdomen; the first bears two large eyes and a complex masticatory apparatus. The thorax is of three segments, and in the male bears three pairs of legs and two of wings; the front pair of the latter are hardened into elytra or wing cases, which, when the animal is at rest, cover and protect the soft flying wings. The female is wingless. The abdomen is of ten segments, and the only appendages are two small ones on the last segment. The animal breathes by a series of tubes ramifying through the body, and which open to the exterior by 20 pairs of "spiracles." The heart is a straight tube running along the back. The alimentary system is very well developed and complex. The nervous system consists of a ganglion above the mouth, from which proceeds a double chain of ganglia along the ventral side. As its name (Periplaneta orientalis) implies it is not indigenous to England, but has been imported from the East. The West Indian "Drummer," which belongs to the same family (Blattidae) also occurs occasionally in England. The cockroach takes about six years to reach maturity.