THE MEMBRANACEA. 399 



In this country most certainly the Bed-bug is 

 always apterous, that is to say, the first pair of wings 

 is represented only by a little pair of convex scales 

 which may be seen at the base of the abdomen, and 

 the hinder wings are entirely wanting ; but we are 

 told that in some countries, especially in hot climates, 

 the Bugs acquire perfect hemelytra and wings. This, 

 of course, is not impossible, but such specimens have 

 never been brought to Europe. Most of the insects 

 of the tribe to which the common Bug belongs possess 

 these organs in full perfection, although they do not 

 appear to use them so freely as those of the preceding 

 groups. The rostrum is composed only of three joints, 

 and is received during repose in a sort of canal formed 

 by a pair of small ridges which run down the breast 

 between the bases of the legs. In the form of the 

 body these insects are always very flat, a structure 

 which enables many of them, like the Bed-bug, to 

 creep into very small crevices, and a considerable 

 number live beneath the bark of trees, where a de- 

 pressed form is absolutely necessary, and so thin and 

 membranous is the structure of the majority, that the 

 name of MEMBRANACEA is given to the tribe. 



Little is known of the habits of many of these in- 

 sects, but I think it probable that the species which 

 live under the bark of trees may be carnivorous in 

 their habits, sucking the juices of other insects which 

 abound in the same situations. The greater part of 

 the species of the group, however, which are mostly 

 of very small size, are found in the open air upon 

 various plants, the juices of which furnish them with 

 nourishment, and each species is usually confined to 

 one or two plants. One of the most abundant is the 

 Monanthia Cardui, which may be found plentifully 



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