92 AN INTRODUCTION TO ENTOMOLOGY. 



Family II. 



(Cockroackts.) 



The cockroaches are such well-known insects that there is but 

 little need for a detailed account of their characteristics. As already- 

 indicated in the table of families, the body is oval and depressed ; 

 the head is nearly horizontal, and wholly or almost wholly withdrawn 

 beneath the pronotum ; the head is bent so that the moutli parts 

 project caudad between the bases of the first pair of legs; the 

 antennae are long and bristle-like; and the pronotum is shield-like. 

 This family includes only the cockroaches; but these insects are 

 known in some localities as " black beetles," and our most common 

 species in the Northern cities bears the name of Croton-bug. 



In the Northern States our native species are usually found in 

 the fields or forests under sticks, stones, or other rubbish. Hut cer- 

 tain imported species become pests in dwellings. In the wanner 

 parts of the country, however, native and foreign species alike swarm 

 in buildings of all kinds, and are very common out of doors. 



Cockroaches are very general feeders: they destroy nearly all 

 forms of provisions, and injure many other kinds of merchandise. 

 They often deface the covers of cloth-bound books, eating blotches 

 upon them for the sake of the sizing used in their manufacture; and 

 I have had them eat even the gum from postage-stamps. They 

 thrive best in warm, damp situations ; in dwellings they prefer the 

 kitchens and laundries, and the neighborhood of steam and water 

 pipes. They are chiefly nocturnal insects. They conceal themselves 

 during the day beneath furniture or the floors, or within the spa 

 in the walls of a house ; and at night they emerge in search of food. 

 The depressed form of their bodies enables them to enter small 

 cracks in the floors or walls. 



Not only are these insects very destructive to our possessions. 

 but owing to their fetid odor merely the sight of them awakens dis- 

 gust ; but it is due them to state that they are said to devour greedily 

 bed-bugs. This will better enable us to abide their presence in our 

 state-rooms on ocean voyages, or in our chambers when we are 

 forced to stop at poor hotels. 



It is a curious fact in the life-history of cockroaches that the 

 female lays all of her eggs at once, they being inclosed in a purse- 



* Blittidae: bldtta, a cockioach. 



