FAMILY BLATTID^. 141 



The arrangement seems to be clear and satisfactory, and yet it will be seen, as in most 

 other arrangements, that the lines of demarkation are imperfectly drawti ; for in the section 

 containing the cockroaches and earwigs, the insect possesses the power of flight : still it 

 is probably sufficient for all practical piu-poses. 



Some of the species of orthopterous insects are extremely proliiic : thus cockroaches 

 become innumerable, and locusts appear in clouds that darken the sky ; and, even in our 

 own more favored countrj', who has not seen the red-legged grasshopper multiply to such 

 an extent as to devour all the herbage of hundreds of acres ! 



Blatticla?. 



This family (Cursoria, the runners) is represented by the well-known and troublesome 

 cockroach. The body is oval, liattened : wings coriaceous, with their inner margins over- 

 lapping each other. The thorax is large, often concealing the head : antennae long, simple 

 and setaceous, being formed of from fifty to one hundred and fifjy joints ; mandibles 

 short, stro!%, and toothed at the tip ; upper lip entire ; labium bifid ; eyes kidney-shaped ; 

 legs long, formed for running ; tarsi five-jointed ; abdomen furnished with two articulated 

 processes. The males are smaller than the females. 



We have 'several species of cockroach, which either inhabit fields or woody places. The 

 common domestic one {Blatta orientalis) is an imported kind, and is very troublesome in 

 basements, cellars, etc. ; while the former, or indigenous species, never comes into our 

 dwellings. 



The methods that have been proposed for destroying the domestic cockroach are nume- 

 rous : they consist in the use of substances which are generally poisonous, and therefore 

 should be used with due precaution. Arsenic, red lead, or other mineral poisons may be 

 mixed with mashed potatoes or meal, and set upon the shelves, floors, etc. frequented by 

 the insects ; and as they are fond of almost every kind of vegetable mixture, they greedily 

 devour the mess, and are speedily poisoned. 



These insects penetrate the most hidden parts of a building, even into the brick work 

 of walls, where their young are frequently produced. They sometimes disappear from the 

 premises without any known cause : at other times, their numbers greatly diminish in a 

 short period of time. 



Blatta nivea. ( Plate xlvi, fig. 7.) 



' Head and antennae yellow ; thorax and abdomen pale green ; wings and wing-covers 

 white and transparent ; legs and underside of the abdomen pale yellowish green ' 

 (Drury, Vol. ii, p. 39, f. 1). 



