HEMIPTERA 391 



stink-bugs on account of their fetid odor, which they are apt to 

 impart to the berries over which they crawl. This nauseous odor is 

 caused by a fluid which is excreted through two openings, one on 

 each side of the lower side of the body near the middle coxae. 



The harlequin cabbage-bug, Murgdntia histrionica. — Among the 

 species of the Pentatomidae that feed upon cultivated plants, the 

 harlequin cabbage-bug or "calico-back" is the most important pest. 

 It is very destructive to cabbage and other cruciferous plants in the 

 Southern States and on the Pacific Coast. It is black, with bands, 

 stripes, and margins of red or orange or yellow. Its bizarre coloring 

 has suggested the popular names given above. The full-grown bugs 

 live through the winter, and in the early spring each female lays on 

 the under surface of the young leaves of its food-plants about twelve 

 eggs in two parallel rows. The eggs are barrel-shaped and are white 

 banded with black. The young bugs are pale green with black spots. 

 They mature rapidly; and it is said that there are several generations 

 in one season. 



This is an exceedingly difficult species to contend against. Much 

 can be done by cleaning up the cabbage stalks and other 

 remnants as soon as the crop is harvested, and, in the 

 following spring, trapping the bugs that have hiber- 

 nated by placing turnip or cabbage leaves in the in- 

 fested gardens or fields, or by planting trap-crops of 

 mustard or other cruciferous plants. The bugs that 

 are not collected by these methods and their eggs 

 should be collected by hand; this can be easily done Fig. 455.- Po<i- 

 as both the bugs and their eggs are conspicuous. ""■^ . "^^'^«^«- 



As if to atone for the destruction caused by their Gi^ve^r.) ^°"^ 

 relative, the harlequin cabbage-bug, there are many 

 members of this family that aid the agriculturist by destroying 

 noxious insects. The species of the genus Podisus have been reported 

 often as destroying the Colorado potato-beetle, currant worms, and 

 other well-known pests. Figure 455 represents a member of this 

 genus, Podisus maculiventris 



Family CYDNID^ 

 The Burrower-Bugs and the Negro-Bugs 



The Cydnidce is the second of the series of families in which the 

 antennae are five-jointed. In this family the outline of the body is 

 more generally oval, rounded, or elliptical, and the form more convex, 

 than in the Pentatomidae. The scutellum is large but varies greatly 

 in size and in outline. Each lateral margin of the scutellum is fur- 

 nished with a furrow into which the margin of the hemelytron of 

 that side fits. In this respect the Cydnidae agrees with the preceding 

 family and differs from the following one. The tibiae are armed with 

 strong spines. 



The family includes two well-marked subfamilies. 



