HEMIPTERA HETEROPTERA. 
165 
11. Gereis odontogastee. 
Genis lacustris, var. e. Lair. Gen. iii. 133 — Hydrometra odontogaster, Zell. 
H.-Sch. Warn. Ins. ix. 73, pi. 301, f. 931. Fieb. Fur. Hem. 109 — 
Limnotvechus odontogaster, Stal. 
North and Middle Europe. 
12. Geeris aegentata. 
Gerris argentata, Schum. Beilr. ii. 49. H.-Sch. Nom. Fnt. i. 63 — Hydro- 
melra argentata, H.-Sch. IVanz. Ins. ix. 74, pi. 301, f. 932. 'Flor. 
Rhyn. Liv. i. 740. Fieb. Fur. Hem. 109. Dougl. and Scott, Hem. 
568 — Limnotrechus argentatus, Stal. 
Middle Europe. 
13. Gereis Servillei. 
Hydrometra Servillei, Meyer, Grei-Gessner. Millh. Schweiz. Fnt. Ges. 
1864, 228 — Limnotrechus Servillei, Stal. 
Switzerland. 
14. Gerris abbreviata. 
Hydrometra abbreviata, Fabr. Syst. Rhyn. 258. Stal, Hem. Fabr. i. 130. 
Pyrenees. 
North America. 
15. Gereis apteea. 
aptera, Schum. 
a — d. Illinois. Presented by F. Walker, Esq. 
e — h. Indiana. Presented by F. Walker, Esq. 
16. Gerris franciscana. 
franciscana, Stal, Fug. Resa, Hem. 265. 
California. 
17. Gerris orba. 
orba, Stal, Fug. Resa, Hem. 264. 
California. 
18. Gereis robusta. 
Hygrotrechus robustus, Pack. Amer. Journ, Sci. 1871. 
California. 
West Indies. 
19. Gerris marginata. 
raiirginatus, Guer. Icon. B. An. Ins. 351, pi. 57, f. 2; Sagra, Hist. Cuba, 
Ins. 415. 
Cuba. 
