ORDER HEMIPTERA. 



73 



family are small, dull-coloured insects, always found in the 

 neighbourhood, though they are not strictly aquatic. 



Fa7nily ii, Hydrovutridce. — The habits of most of these insects 

 are herbivorous, and they are all found near water. 



Hydro77tetra stagnorum is a black or brown insect, more or less 

 tinged with reddish, and about half an inch long. It is found 

 running on the surface of water, or else on the banks or among 

 water plants, but is not so active as some of the other species. 



Halobates Pictus (Mag.) 



Family 12, Gerridce. — This family includes some very familiar 

 insects, which may be seen running over the surface of every 

 piece of water. These insects, of which several species are 

 abundant in Britain, have boat-shaped bodies. The typical form 

 is Gerris lacustris, which may be met with almost anywhere. 

 They are predaceous in their habits, feeding upon other insects. 

 Some nearly allied, but mostly very small species, with legs even 

 longer in proportion than those of our common forms, are met 

 with at sea within the tropics, and often at a great distance from 

 land. 



