222 SUMMER 



but a kind of bug, akin to the flat-backed shield bugs which 

 are often found seated in summer on heads of umbelliferous 

 and other plants. Their main family characteristic is the 

 possession of a beak for sucking instead of jaws. Water- 

 boatmen swim on their backs, and propel themselves with 

 their hind pair of legs, which are enlarged to serve as 

 oars. Their trips to the surface of the water are not mere 

 sallies of inquisitiveness ; they must come up periodically 

 to breathe. Water-scorpions and pond-skaters belong to the 

 same beaked tribe. The voracious water-scorpion, which 

 is common in slowly flowing ditches, has the forelegs strongly 

 developed to help it in catching its varied prey, and holding 

 it for the beak to suck. Pond-skaters are surface-feeding 

 insects, and altogether more attractive. All through the 

 summer their light forms dart rhythmically in parties over 

 the surface of ponds and quiet streams ; they are one of 

 the most animated forms of summer life, and as welcome on 

 the river as the monkey-flower, or the song of the sedge- 

 warbler. Another conspicuous summer insect of the same 

 tribe is the frog-hopper, which lives in the foam-bubbles 

 hanging to the stems of sorrel and other herbs in May. It 

 blows these clots of ' cuckoo-spit ' from the sap sucked out 

 of the plant ; if we search inside them, we shall find the 

 tender green insect, sheltered from the sun in its tabernacle 

 of moist bubbles. In June and July, when the ' cuckoo-spit' 

 has evaporated from the grasses, picnickers and campers 

 meet the frog-hopper again. It is characteristic of this 

 tribe of bugs not to show such marked and astonishing 

 changes of structure as butterflies, for example, undergo 

 between the egg and the winged insect; and the adult 

 frog-hopper of the dry summer pastures is easily recognisable 

 as the mature form of the soft green creature in the ' cuckoo- 

 spit.' It is larger, tougher, and less vividly green ; but it 



