276 PHYTOPHAGA, [ Donacia. 
D. cinerea, Herbst. (hydrocheridis, F.). This species may be 
distinguished from all the rest of the British Donacie by having the 
upper surface thickly clothed with greyish-silvery pubescence, so that 
the insect presents a dull and mealy appearance; the only other 
European species that resembles it in this respect is D. tomentosa ; the 
under-side is silvery; it is elongate, sublinear and depressed, of a 
greenish or reddish coppery colour, with the antenne dark, the base of 
the joints being more or less ferruginous, and the legs metallic, partially 
ferruginous; head and thorax very closely sculptured, the latter sub- 
quadrate with the anterior angles scarcely prominent ; elytra subparellel, 
widest about middle, with the apices rounded or very obtusely truncate, 
feebly impressed on disc near suture, with comparatively finely punc- 
tured striz, interstices closely rugose ; posterior femora simple in both 
sexes. L. 7-10 mm. 
Male with the last ventral segment subtruncate at apex and impressed, 
female with the same segment rounded at apex. 
~ On aquatic plants, Sparganium, Typha latifolia, Arundo phragmites, &c., in 
May and June; rare; Woolwich; Surrey Canal; Woking (banks of Basingstoke 
Canal); Faygate, Sussex; Winchelsea; Deal; Swansea; Bristol; Yorkshire ; 
Northumberland district, Prestwick Carr (Wailes). 
D. sericea, L. (levicollis, Thoms.; profeus, Steph.). Convex, 
rather short, broader in male than in female, upper surface shining, 
rarely dull, strongly metallic, very variable in colour, presenting all 
shades of coppery, greenish-coppery, «neous, green, blue, blue-black, 
crimson, &c. ; the base of the antennw and the legs are concolorous with 
the upper side ; under-side silvery ; head thickly punctured, with the 
frontal furrow deep, antenne rather long, with the third joint elongate, 
twice as long as second; thorax longer than broad, narrowed behind, 
very closely sculptured, with the anterior angles acute and reflexed and 
the lateral callosities strongly defined ; elytra broadest at shoulders, 
distinctly impressed, with moderately strongly punctured strie, the 
punctures being connected by transverse wrinkles, and the interstices 
besides these being more or less distinctly rugose, apices rounded or 
obtusely truncate ; legs moderately long, femora with a strong triangular 
tooth in both sexes. L. 7-95 mm. 
Male with the first ventral segment of abdomen broadly impressed at 
apex, and the fifth impressed and truncate at apex, female with the fifth 
segment rounded at apex. 
On aquatic plants; common and generally distributed from the northern midland 
counties southwards; less common further north ; Scotland, not common, Solway, 
Tweed, Forth, Dee, and Moray districts ; Ireland, near Dublin and Armagh, and 
probably widely distributed. 
D. discolor, Panz. (comari, Suffr. ; proteus, Kunze ; geniculata, 
Thoms.). Very closely allied to the preceding in shape, colour, and 
general structure and sculpture ; it may, however, be easily known by 
