GRASSHOPPERS AND THEIR RELATIVES 319 



cockroaches, they place the wings over the abdomen 

 when at rest. 



6. The cockroaches or Blattidse constitute a large cockroaches 

 group of insects, most abundant in the tropics. One 

 species is extremely common in houses in England, 

 where it is known as the black beetle, although it is 

 dark brown, and is not a beetle. In Central America 

 some of the cockroaches are over 3 inches long and 

 fully if inches broad. These are repulsive creatures, 

 but there is a small, delicate green species, often found 

 in bunches of bananas, which is rather attractive. 

 Superficially, cockroaches seem to have no head, that 

 member being hidden under the large thoracic plate. 

 The broad wings, with very numerous veins, are folded 

 over one another across the back, presenting a flat 

 surface from above. The hind legs are not adapted' for 

 jumping, nor are there any musical organs. The long, 

 slender antennae have very many joints. Cockroaches 

 were abundant in later Paleozoic times, many millions 

 of years ago. A fossil wing is figured on page 151. 

 Forty-three living species of cockroaches are known 

 from the United States, but they are mostly Southern, 

 and ten have probably been introduced through human 

 agencies. 



References 



SCUDDER, S. H. Guide to the Genera and Classification of the North American 



Orthoptera. E. W. Wheeler, Cambridge, 1897. 

 WALDEN, B. H. Euplexoptera and Orthoptera of Connecticut. Connecticut 



Geological and Natural History Survey, Bulletin 16, 1911. 

 BLATCHLEY, W. S. Orthoptera of Indiana. Indianapolis, 1903 



