Bugs, Cicadas, Aphids, and Scale-insects 199 



for some time under water. Both kinds are attracted to lights, and may 

 often be seen- in summer about outdoor electric lamps. The eggs of the 

 water-boatmen are attached to the submerged stems of aquatic plants, while 

 those of the back-swimmers are inserted in the stems, the female having 

 a sharp ovipositor for this purpose. In winter the adults lay dormant in the 

 mud at the bottom of ponds or streams. 



All the species of water-boatmen in the country belong to the genus 

 Corisa, while there are three genera of back-swimmers, Notonecta, with 

 hind legs longer than the others and fore wings but little longer than the 

 abdomen, being the most abundant and 

 wide-spread. Plea is a genus with all the 

 legs alike, while Anisops, the third genus, 

 has the wing-covers usually much longer 

 than the abdomen. The complete life- 

 history of no member of either of these 

 families of water-bugs is yet known, but it 

 ought not to be a difficult matter for some 



persistent observer to add this needed ,-. ~ . 



FIG. 274. A water-boatman, Corisa 



knowledge to entomological science. Both sp. (After Jenkins and Kellogg; 

 water-boatmen and back-swimmers live twice natural size -) 

 readily in aquaria, and make thoroughly interesting creatures to observe 

 at leisure. The characteristic habits of obtaining air, swimming, capturing 

 prey, etc., can all be learned from the observation of aquarium specimens. 

 The capacity of the water-boatmen to remain below the surface in pure 

 water for protracted periods, apparently indefinitely long, needs to be better 

 understood than it is at present, and should be an interesting problem for 

 some observer of aquarium life. 



Creeping or crawling about among the stems and leaves of submerged 

 plants in reedy and grassy quiet waters, and feeding on smaller insects, may 

 sometimes be found certain small flat-bodied oval insects with front legs 

 thickened and fitted for grasping. These are water-creepers, or Naucoridae, 

 only five species of which are known in this country. The single species 

 found in the eastern states is known as Pelocaris jemorala, and is about 

 ^ inch long, broadly oval in shape, and yellowish brown in color. The 

 other species belong to the genus Ambrysus and are restricted to the western 

 states. The life-history of but one member of this family is known. 



Occasionally there will be seen resting, or swimming slowly about, at the 

 bottom of the pool a veritable giant bug, 2\ inches long and i^ inches wide, 

 with heavy strong legs flattened and oar-like and the front ones held out 

 arm-like and bent in an expectant grasping position. Again, in the warm 

 sultry evenings of midsummer and early autumn, among the swarms of 

 insects attracted to the electric lights on the streets, one or two great bugs 



