378 AN INTRODUCTION TO ENTOMOLOGY 



and the hemelytra are almost always fully developed and are furnished 



with an emboliirm (Fig. 433). As in the following family, the beak 



consists of three segments; the 

 antennse, of four; and the tarsi, 

 of three. 



The species are small. They 

 are found in a great variety of 

 situations, often upon trees and 

 on flowers, sometimes under bark 

 or rubbish. They are predacious. 

 Fig- 433.— Hemelytron of Triphelps. Thirty-six species have been 



catalogued in our fauna; these 



represent thirteen genera. The following species will serve as an 



example. 



The insidious flower-bug, Triphelps insidiosus. — This is perhaps 

 the best-known of our species. It is a small black bug, measuring 

 only 2 mm. in length; the hemelytra are yellowish white on the 

 corium, at the tip of which is a large, triangular, blackish spot; the 

 membrane is milky white. This species is widely distributed; it is 

 common on flowers, and is often found preying upon the leaf -inhabit- 

 ing form of the grape Phylloxera; it is also often found in company 

 with the chinch-bug, upon which it preys and for which it is some- 

 times mistaken. 



Family CIMICIT>M 



The Bedbug Family 



The members of this family are parasitic bugs, which are either 

 wingless or possess only vestigial hemelytra. In these insects the 

 ocelli are absent, the antennce are four-jointed, the beak is three- 

 jointed, and the tarsi are three-jointed. Only four species belonging 

 to this family have been found in America north of Mexico. These 

 can be separated by the following table, which is based on a more 

 detailed one given by Riley and Johannsen ('15). 



A. Beak short, reaching to about the anterior coxae. 



B. Pronotum with the anterior margin very deeply sinuate. The genus Ctmex. 

 C. Body covered with very short hairs; second segment of the antennae 

 shorter than the third; hemelytra with the inner margin rounded and 

 shorter than the scutellum. The common bedbug. . .C. led uldrius 

 CC. Body covered with longer hairs; second and third segments of the an- 

 tennae of equal length; hemelytra with the inner margin straight 

 and longer than the scutellum. Species found on bats. . .C.pilosellus 

 BB. Anterior margin of the pronotum very slightly sinuate or nearly straight 

 in the middle. Species found in swallows' nest?,. . .CEclacus vicar ius 

 AA. Beak long, reaching to the posterior coxae. Infests poultry in southwest 

 United States and in Mexico Hcematosiphon inodorus 



The common bedbug, Clmex lectuldrius. — The body is ovate in 

 outline and is very flat (Fig. 434) ; it is reddish brown in color, and is 

 4-5 mm. long by 3 mm. broad when full-grown. This pest is a noc- 



