RHYNCOTA. 31 



are two other genera which belong to this family, viz. : 

 Naiicoris and Ranatra, both of which genera are 

 represented by a single British species, the iV. cimicoides, 

 which has very thick pincer-like fore-legs, and is an 

 excellent swimmer ; and the B. linearis, a long stick- 

 like cylindrical creature, 18 lines long exclusive of its 

 spiracular tail filaments, which are alone 15 lines long; 

 it has long nipper-like feet with habits similar to the 

 Water-Scorpion. 



The second section (Aurocorisa) contains several 

 families, but I shall only take a short notice of the 

 Hydrometridiv or Water-Measurers, Cimicidce, the Bed- 

 bug family, the Reduviidw, and the Lygoeidw. Every 

 one who has wandered by a stream or river, or loitered 

 on the bank of a pool, must be acquainted with the 

 forms of certain long and lanky creatures of a dark 

 colour with slender legs, with which they skim or skate 

 along the surface of the water. These are Water- 

 Measurers {Hydrometrce), a very appropriate term, for 

 they take four or five quick steps and then stop, then 

 on again and stop. There are four or five species, of 

 which the commonest, perhaps, is H. Gihhifera and 

 H. lacustris ; they are generally about 4^- to 5j- lines in 

 length ; they feed on small insects that may happen to 

 come in their way, which they catch with their pre- 

 hensile fore-legs. In many, if not most individuals the 

 wings are imperfectly developed, in fact, they are often 

 altogether absent — but these apterous individuals are as 

 capable of reproduction as the winged. The underside 

 of the bodies of the Hydrometra are often clothed with 

 a fine coating of plush, which serves to repel the action 

 of the water and to facilitate locomotion. A smaller 



