372 RHTNCHOPHORA. [Rhwoncue. 



constricted in front, with a central channel and a lateral tubercle on 

 each side, anterior margin scarcely raised ; elytra with evidently deeper 

 and stronger striae and more convex interstices than in R. castor, with 

 the asperities more remote. L. 2-2f mm. 



Male with the posterior tibiae armed with a hook. 



Marshy places ; bv sweeping herbage ; also in flood refuse; according to Bedil 

 it is attached to species of Polugonum ; the larva has been observed by Buddeberg 

 in the stems of P. lapathifolium vars. nodosum and incanum ; not common ; 

 Wimbledon (Champion) ; Horst-11 (Power) ; Ash wick en, Norfolk (Power) ; London 

 district and Bristol (Stephens) ; I have found a few specimens at Lincoln in flood 

 refuse in autumn, but know of no record further north. 



XI. dcnticollis, Gyll. A small and inconspicuous species which 

 may be known from all the preceding by the fact that the anterior 

 margin of the thorax is furnished with two raised tubercles in middle 

 placed near one another; oblong ovate, convex, black, antennae and legs 

 more or less ferruginous, the tibiae being always reddish ; underside 

 thickly covered with greyish scales, of which there is also a patch at the 

 base of suture of elytra; the rest of the upper surface in fresh specimens 

 is sprinkled with whitish scales, but they are very easily rubbed off as 

 appears also to be the case with the scutellary patch ; thorax compara- 

 tively long, very coarsely punctured, scarcely at all constricted in front 

 and with a central channel and a rather strong lateral tubercle on each 

 side behind ; elytra with rather deep punctured striae, interstices rather 

 convex, finely rugose or scratched ; legs moderately long. L. 1^-2 mm. 



Chalky and sandy places by sweeping herbage ; sometimes found in moss ; rare ; 

 London district, ra'her widely distributed but always rare, Shirley, Mickleham, 

 Forest Hill, Box Hill, Chattendeu, Walton-on-Thauies, Chatham; Hythe ; Holm 

 Bush, Brighton ; New Forest ; Windsor Forest, rare (S. Stevens). 



This species is most closely allied to Phytobius quadrinodosus from 

 which, according to M. Bedel, it can only be distinguished by the 

 generic characters ; my single specimen, however, is very different in 

 appearance, having the sides of the thorax much straighter, with the 

 surface more coarsely and less closely punctured, and the elytra much 

 narrower in proportion to the thorax, with the shoulders rounded and 

 not prominent and the interstices much less asperate ; the striae also are 

 deeper and more strongly punctured. 



EUBRYCKIITS, Thomson. 



The single species which forms this genus occurs both in Europe and 

 North America, and is distinguished from the two following, which 

 resemble it in their aquatic or subaquatic habits, by having the tibiae 

 and tarsi furnished sparingly with long natatory cilia ; the tarsi are 

 elongate, with the three first joints compressed and not tomentose 

 beneath, and the last very long ; the tarsal claws are simple and stout ; 

 the anterior coxte are almost contiguous ; the antennae are ten-jointed, 



