THE BED-BUG 289 



the glands by which the volatile fluid is secreted which 

 imparts to the insects the disagreeable odour they are 

 noted for. The glands open by a very fine aperture 

 situated beneath a kind of flap, which runs from the 

 meso-thorax down between the coxae of the hind legs. 



In the possession of these odoriferous glands the bed- 

 bug is by no means exceptional ; it is one of the usual 

 characteristics of the order, and the odour of some of the 

 larger wild species is far more powerful, though of the 

 same class. The liquid secreted is a colourless oily sub- 

 stance, and it would appear to be continually being given 

 off during life. Its smell is of a compound nature, and 

 a keen-scented person will detect, underlying the more 

 disagreeable elements, the scent of a freshly cut cucum- 

 ber. That the disagreeable character of the bed-bug's 

 secretion is not due to the animal nature of its food 

 appears from the fact that a precisely similar odour is 

 exhaled by those species that subsist on vegetable juices. 

 In some wild species the fluid seems to be of a different 

 constitution, as it is quite pleasantly fragrant. Coranus 

 subapterus, for example, a grey species which is found 

 running on the ground in heathy and sandy places, ex- 

 hales, when handled, a perfume which has been compared 

 to that of jargonelle pears. But of whatever nature the 

 scent may be, it is no doubt protective in function, and 

 the insects are by its presence rendered nauseous and dis- 

 tasteful to birds and other enemies. The bed-bug does 

 not seem, however, as it is now circumstanced, to derive 

 much protection from its odour, for, apart from its pre- 

 sence being thus plainly advertised to man, the common 

 cockroach will, notwithstanding the smell, devour it with 

 avidity; and no doubt tragedies of this kind are of nightly 

 occurrence in the slums of seaport towns, where both of 

 these intruders have taken up their quarters and multiplied 



