RHYNGOTA. 29 



Underneath tlie prettily-marked wing-cases of the 

 boatman you may see, by examination, a pair of large 

 hyaline wings which the possessor uses when so inclined. 

 Though when sunning itself on the surface of the 

 water, Notonecta generally lies on his back, he can 

 swim equally well with the keel up, and first turns on 

 one side then on another with great rapidity. The 

 larva and pupa resemble the imago, except that the 

 former has not a vestioje of wino^s, and the latter has 

 rudimentary ones. Tlie boatman's length is from 7 to 

 8 lines. There are other genera allied to Notonecta, as 

 Flea, Corixa, Cijmitia, and Sigara, all of which are 

 good swimmers. Of Plea there is only one Britisli 

 species, viz., P. minutlssima, which is not much above 

 a line in length ; it is common in stagnant waters. Of 

 the other genera, Gorixa Geoffroyi, about 5 lines long, 

 is extremely common in stagnant waters ; its form 

 must be more or less familiar to every one who has 

 stood on a bank and watched the fishing-net hauled in, 

 when hundreds of these little smoky-bLack insects are 

 jumping about in every direction, as not knowing what 

 has happened to them. To the right of the boatman 

 will be seen a curious scorpion-like creature (Fig. 11) 

 with its fore-legs extended pincer-like, in a threatening 

 attitude ; this is the Nepa Cinerea or Water-Scorpion, 

 which I have taken to illustrate the family of Nepidcc. 

 This insect is a dull dingy-looking creature with a small 

 pointed head, scorpion-like fore-legs, and a tail with two 

 long bristle-like projections ; it is nearly an inch long, 

 not including the tail. It is painfully sluggish in its 

 movements, and on watching it one is impatiently 

 prompted to say with the policeman, '' Move on — Move 



