200 AN INTRODUCTION TO ENTOMOLOGY. 



are very common. Here we find the body extended laterally into 

 angular or rounded projections, suggesting the name of the typi- 

 cal genus. But the most striking character which distinguishes this 

 group is the remarkable form of the front legs. These are fitted for 

 seizing prey. The coxa is somewhat elongated ; the femur is greatly 

 thickened, so that it is half or two thirds as broad as long ; the tibia is 

 sickle-shaped, and fits closely upon the broadened and curved end 

 of the femur ; both tibia and femur are armed with a series of close- 

 set teeth, so that the unlucky insect that is grasped by this organ 

 is firmly held between two saws ; the apparently useless tarsus is 

 bent back into a groove in the tibia. Another striking character 

 is presented by the antennae : the terminal segment is more or less 

 enlarged into a knob. Under the lateral margin of the pronotum 

 there is on each side a groove into which the antenna fits. 



Only two genera are represented in our fauna. These can be 

 distinguished as follows: 



A. Scutellum short; head with a bifid prolongation above the insertion of the 

 antennae. Phymata. 



AA. Scutellum very long, extending to the tip of the abdomen ; head without 

 bifid prolongation of the antennae. Macrocephalus. 



Our most common species is Phymata Wolffii (Fig. 169). It is 

 a yellow insect, greenish when fresh, marked by a broad 

 black band across the expanded part of the abdomen. 

 It conceals itself in the flowers of various plants, and cap- 

 tures the insects which come to sip nectar. It is remark- 

 able what large insects it can overcome and destroy. 

 Cabbage-butterflies, honey-bees, and large wasps are 

 overpowered by it. 



Family XXV.— Aradid.£.* 



The Aradid<z are very easily recognized by the depressed form 

 of the body. In fact they are the flattest of all Heteroptera. They 

 live in the cracks or beneath the bark of decaying trees ; and the 

 form of the body is especially adapted for gliding about in these 

 cramped situations. They are usually of a dull brown color ; some- 

 times they are varied with reddish or pale markings. Unlike the pre- 

 ceding family, the legs are all of similar form. There are no 

 ocelli ; the antennae are four-jointed ; the rostrum three-jointed ; the 

 wing-covers are usually well developed, with distinct corium, clavus, 



* Aradidae, Aradus: aradus (dpdSoS), a violent disturbance of the stomach. 



