96 FAMILY II. BLATTID.E. THE COCKROACHES. 



ments will elapse before the last of the busy marauders will have 

 disappeared. Of this and other species Marlatt (1902) has 

 written : 



"The damage they do is not only in the products actually consumed, 

 but in the soiling and rendering nauseous of everything with which they 

 come in contact. They leave, wherever they occur in any numbers, a fe- 

 tid, nauseous odor, well known as the 'roachy' odor, which is persistent, 

 and can not be removed from shelves and dishes without washing with 

 soap and boiling water. Food supplies so tainted are beyond redemption. 

 This odor comes partly from their excrement, but chiefly from a dark 

 colored fluid exuded from the mouth of the insect, with which it stains its 

 runways, and also in part, doubtless, from the scent glands, which occur 

 on the bodies of both sexes between certain segments of the abdomen, and 

 which secrete an oily liquid possessing a very characteristic and disagree 

 able odor. It frequently happens that shelves on which dishes are placed 

 become impregnated with this roachy odor, and this is imparted to and re- 

 tained by dishes to such an extent that everything served in them, particu- 

 larly liquids, as coffee or tea, will be noticed to have a peculiar, disgust- 

 ing, foreign taste and odor, the source of which may be a puzzle and will 

 naturally be supposed to come from the food rather than from the dish.' 



The Oriental roach is probably the most carnivorous of all our 

 Blattidse, though, like most others, it is fond of starchy food. Tt 

 is known to feed upon meat, cheese, woolen clothes, and even old 

 leather, and is said to be especially fond of the festive "bed-bug," 

 AcantMa lectularia L., which soon disappears from a house infest- 

 ed with the Oriental roach. This roach is, however, far too great 

 a nuisance in itself to be introduced as a means of eradicating 

 even the bed-bug. 



The eggs of the Oriental roach are sixteen in number, and the 

 large, horny capsule or ootheca in which they are packed is car- 

 ried about by the mother for a week or longer when she drops it 

 in a warm and sheltered place. Along one side of the capsule, 

 which resembles in form and color a diminutive seed of the papaw, 

 Asiiuhia triloba Duval, is a seam where the two edges are cement- 

 ed closely together. When the young are hatched they excrete a 

 liquid which dissolves the cement and enables them to escape with- 

 out assistance, leaving their infantile receptacle as entire as it 

 was before they quitted it. 



This species is notably gregarious in habit, the individuals liv- 

 ing together in colonies in the most friendly way, the small ones 

 being allowed by the larger ones to sit on them, run over them and 

 nestle beneath them without a show of resentment. The young 

 pass through a variable number, sometimes as many as seven, 



