Donacia. | PHYTOPHAGA. 
b*. Interstices of elytra at base not, or 
scarcely, punctured; average size 
smaller. 
at. Form more elongate ; upper surface 
duller and less evidently impressed ; 
teeth of posterior femora ARDS and 
distinct 
bt. Form shorter ; upper surface more 
shining and more evidently im- 
pressed ; teeth of posterior femora 
indistinct é 
3. Posterior femora of male without teeth, 
A. Elytra sharply truncate or emarginate at 
apex, with both the apical angles well 
marked. 
a. Elytra without reddish-purple stripe 
near suture; anterior angles of thorax 
more prominent’. 5. 5 « + « 
b. Elytra with a reddish-purple and blue 
stripe near suture; anterior angles of 
thorax less prominent . . . 
B. Elytra obtusely truncate or separately 
rounded at apex, the exterior angles at 
least being rounded. 
a. Length 7-12 mm.; thorax transversely 
wrinkled, shining, sometimes almost 
SNORT oo Gog 6 6 6 oe lo eo 8c 
b. Length 6-9 mm.; thorax closely and 
strongly punctured. ..... . 
ii. Upper surface thickly pubescent; posterior 
femora without teeth, and not reaching apex of 
HEE IG Rieter nao tie eo cj a ec oe 
II. Tibie produced externally into a tooth at apex ; 
mandibles stout, projecting considerably beyond 
labrum; first segment of abdomen equal to, or 
rather shorter than, the remainder taken 
together. (S.g. Platewmaris, Thoms.) 
i, Elytra with impressions; legs metallic, uni- 
colorous with body; posterior femora with a 
strong triangular tooth in both sexes. 
1. Antenne longer, with the third joint longer 
im proportion; anterior angles of thorax 
acute and reflexed, and the callosity near 
these angles clearly defined . : 
2. Antenne shorter, with the third joint shorter 
in proportion; anterior angles of thorax 
rounded and deflexed, and the callosity near 
these angles less distinctly defined . . . 
i. Elytra without impressions ; legs red; posterior 
pane with a strong tooth in male and a 
feeble tooth in female. 
D. THALASSINA, Germ. 
D. IMPRESSA, Payk. 
D. SIMPLEX, F, 
(linearis, Hoppe.) 
D. VULGARIS, Zsch. 
(typhe, Abr.) 
D. CLAVIPES, F. 
(menyanthidis, F.) 
D. SEMICUPREA, Panz. 
(simplex, F. (Syst. E1.).) 
D. CINEREA, Herbst. 
(hydrocheridis, F.) 
D. sERicEa, L. 
D. piscotor, Panz. 
(comari, Suff.) 
