FIELD BOOK OF INSECTS. 



or food. They do not breathe through their tail but from 

 it the air passes through hair-covered channels to spiracles 

 on their thorax. Small fish and other aquatic animals 

 are easy prey, and the suctorial beak will pierce even the 

 careless collector's fingers. Doubtless the pearly color 

 of their backs, which, as they swim, is seen against the 

 sky, and the dark of their under (upper) side helps them to 

 approach their victims and to avoid becoming victims. 

 The adults fly well and are frequently attracted to lights. 

 During the winter they sometimes may be seen swimming 

 about in the shallow water in which they habitually live, 

 even though it be covered with ice. It is said that these 

 insects, by rubbing their front legs together, make a noise 

 like the word "chew," twice repeated. The eggs are 

 placed in the submerged stems of aquatic plants. The 

 adults of Plea striola are only about .06 in. long; it is the 

 only species of that genus. Our other species are much 

 larger and, for the most part, belong in Notonecta (Plate 

 XXV). 



SALDID/E 



This family has been called Acanthiidae, but a techni- 

 cality rules out the use of that name. Furthermore, its 

 use would be confusing, as the Saldidse have no intimate 

 connections with bed-bugs but live on the shores of lakes 

 and rivers. Uhler, one of the master Hemipterists, wrote : 

 "In the present family we have types which like Galgulus 

 [Gelastocoris], make holes for themselves, and live for a 

 part of the time beneath the ground. Like the members 

 of that genus too, a majority of them inhabit damp soils, 

 and are often found in countless numbers on the salt or 

 brackish marshes of our sea coasts. Their manner 

 strongly recalls that of the tiger-beetles that inhabit the 

 same places. When approached, or in any way disturbed, 

 they leap from the ground, arise a few r feet into the air, 

 by means of their wings, and alight a short distance away, 

 taking care to slip quickly into the shade of some protecting 

 tuft of grass or clod, where the soil agrees with the color 

 of their bodies." They feed chiefly upon the juices of 

 drowned insects. There are numerous species of Saldula, 

 the principal genus of our region. They are rather soft in 



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