564 



INSECTA— ORDER ORTHOPTERA. 



oval insects, generally more or less flat, with a round or oval thorax, under 

 which the small head is often quite hidden. The antennae 

 Cockroaches are slender, and moderately long, and the legs are 

 (BlattidcE). very spiny. Many species are apterous, at least in the 

 females ; but the majority are winged, the wing-cases being 

 of a parchment-like consistency, and generally more or less overlapping; 

 the wings are transparent. They are nocturnal insects, feeding chiefly on 

 decaying vegetable matter ; but many are carnivorous, our domestic species 

 being particularly fond of bed-bugs. The eggs are deposited in a capsule, 

 and the female may often be seen running about with the capsule pro- 

 jecting from her body. They are nearly always of dull colours, such as 

 grey, reddish-brown, or black. Three species commonly infest our houses, 

 all of which appear to have been imported insects, like most of our house- 

 hold pests. The first and smallest of tliese is Phyllodromia germaniea 

 (Linn.), a pale brown, winged insect, about half an inch long. It is sometimes 

 found in bakeries. The female is said to open the egg-case to allow of the 

 escape of the young. In America, where it is much commoner than with us, 

 it is called the croton bug, and is said to frequent the neighbourhood of 

 water-pipes. Our common cockroach, Blatta orienUdis (Linn.), a reddish- 

 brown insect, with fully developed wings in the male, but only rudimentary 

 wings in the female, is generally called "the black beetle," though it is 



neither black nor a beetle. An- 

 other species, Periplaiieta ameri- 

 cana (Fabr.), which is winged in 

 both sexes, is redder ; the thorax 

 is yellowish-grey, with a large black 

 mark in the centre ; it expands 

 nearly two inches across the wings, 

 and is not uncommon in ware- 

 houses. Cockroaches of various 

 species abound on board ship ; and 

 apart from one or two small in- 

 digenous species (found not in 

 houses, but in woods and fields), 

 many others, besides those which 

 we have mentioned, may be met 

 with in the docks, and elsewhere, 

 some of which may perhaps succeed 

 in establishing themselves in this 

 country. Even specimens belong- 

 ing to the genus £?^6cnis (Serville), 

 which includes the great broad- 

 winged species called "drummers" 

 in the West Indies, have been 

 met with occasionally. These are 

 yellowish-grey, with a large black 

 mark on the middle of the thorax, 

 and measure at least three inches 

 across tlie wings ; but the largest 

 of all the cockroaches belong to the 

 genus Megaloblatta (Dohrn), found 

 in Mexico and South America. They liave longer and narrower wings in 



Fig. 42.— Drummer Copkroacu (Blaicrus 

 gUjanteus, Linn.). 



