274 PHTTOPHAOA. [Donticia. 



head thickly and rugosely punctured ; antennae black, with base 

 metallic ; thorax somewhat longer than broad, closely and deeply 

 punctured, with the lateral callosity moderately distinct, and the 

 anterior angles obtusely dentate ; elytra subparallel until behind 

 middle, feebly impressed near suture, rather strongly punctate-striate, 

 interstices finely rugose, reticulate, apex truncate ; legs uuicolorous, 

 metallic, femora with a sharp tooth in both sexes. L. 7-9 mm. 



Male with the fifth ventral segment subtruncate, and impressed at 

 apex, female with the same segment produced and subacuminate. 



On Scirpus, Carex, &c., in June; not common ; Caterham, Woking, Bearatcd ; 

 Faygate, Sussex ; Pegwell Bay ; Deal ; Hastings ; Portsmouth district ; Bristol. 



D. impressa, Payk. ( ? brevicornis, Kunze, nee Ahr.). Closely 

 allied to the preceding, but shorter, broader, and more shining, with 

 the antennae shorter, and the posterior femora armed with a blunt and 

 more or less obsolete tooth; the thorax is less closely and less deeply 

 punctured, and has the lateral callosity less distinct, and the impres- 

 sions on the elytra are more pronounced ; in the colour both of the 

 under and upper side it much resembles D. thalassina. L. 6|-9 mm. 



On aquatic plants (Carex, &c.\ in Muy ; not common; Maidstone ; Faygate, 

 Sussex (Gorham) ; Sandwich (T. Wood) ; Hastings district ; Bristol ; Bretby Park, 

 liepton (W. Garneys); Scotland, "Ayrshire, Mr. Hardy," Murray's Cat.; this 

 latter record is somewhat doubtful. 



D. simplex, F., Syst. Ent. (linearis, Hoppe ; aruginosa, Westh.). 

 Elongate, depressed, coppery, reddish, or aeneous green, under-side 

 silvery, antennae and legs partly reddish ; head very closely sculptured, 

 thorax slightly longer than broad, very closely and rugosely punctured, 

 with the central furrow more or less obsolete, anterior angles pro- 

 nounced ; elytra long, gradually narrowed to apex in male, more parallel 

 in female, obsoletely impressed, broadly truncate at apex, with rows 

 of rather shallow punctures, interstices closely rugose, giving the 

 insect a frosted appearance ; posterior femora simple in both sexes. 

 L. 7-9 mm. 



On aquatic plants ; generally distributed throughout the kingdom ; it is one of 

 the commonest British species. 



X>. vulg-aris, Zsch. (ti/phce, Ahr.). Allied to the preceding, but, as 

 a rule, easily distinguished by the broad reddish-purple and blue 

 stripe which runs down each elytron near suture ; occasionally uni- 

 colorous specimens occur, but these may be known by the shorter 

 antennae, much less pronounced anterior angles of thorax, and more 

 regular striae of the elytra, which are more parallel and less gradually 

 narrowed behind ; the pubescence of the under-side is a little darker 

 and greyer; the very close sculpture of the thorax and the absence of 

 teeth on the posterior femora in both sexes will distinguish it from D. 

 lhalassina. L. 6-9 mm. 



