STRIDER.) The families Corixithe (tee WATER BOATMAN), Nepidtr (see WATER-SCORPION). Gal gtilithe (see TOAD Bus), and Belw:tomidx (see FISI1KILLER) belong to this group.
The back-swimmers of the family Notonecticke are predaceous water-bugs resembling the water boatmen. hut the dorsum is very convex and they always swim with the ventral surface up ward, a habit which distinguishes them from all other water-bugs. The female pierces holes in the sterns of water-plants for her eggs. The adults hibernate in the mud at the bottom of streams and ponds. About a dozen species are known to inhabit the United States.
The creeping water-bugs of the family Nan corida- are small, flat-bodied, oval water-bugs found in ponds containing plenty of vegetation, on which the creepers crawl, o• about which they swim, feeding upon land-insects which have ac cidentally fallen into the water.
The marsh-treaders of the family Hydro resemble the water-striders, but are 1110r, slender and delicate. The adults of our commonest species (1Iydrometra lineata) hiber nate under rubbish along the banks of slow streams and ponds, and lay their eggs singly, on the stems' of aquatic plants. The larvce fall into the water and remain near the bank. feeding upon the bodies of insects which fall into the stream. The only other true bugs which are in any way aquatic belong to the family Ilebritlx, which contains very small species of semi-aquatic habits, being found in very wet moss and damp littoral vegetation. The common cosmopolitan German cockroaeh croton bug (Ectobin yermaniea) is often called 'the water-bug' in the ITnited States, since it. frequents the vicinity of water-pipes in houses. See