HEMIPTERA HETEROPTEKA. 165 



11. Gerris odontogaster. 



Gerris lacustris, var. e, Lair. Gen. iii. 133 — Hydrometra odontogaster, Zett. 

 H.-Sch. Wanz. Ins. ix. 73, pi. 301, f. 93*1. Fieb. Eur. Hem. 109— 

 Limnotrechus odontogaster, Stal. 



North and Middle Europe. 



12. Gerris argentata. 



Gerris argentata, Schum. Beilr. ii. 49. H.-Sch. Norn. Ent. i. 63 — Hydro- 

 metra argentata, H.-Sch. Wanz. Ins. ix. 74, pi. 301, f. 932. Flor. 

 Rhyn. Liv. i. 740. Fieb. Eur. Hem. 109. Dougl. and Scott, Hem. 

 568 — Limnotrechus argentatus, Stal. 



Middle Europe. 



13. Gerris Servillei. 



Hydrometra Servillei, Meyer, Grei-Gessner. Millh. Schtveiz. Ent. Ges. 

 1864, 228 — Limnotrechus Servillei, Stal. 



Switzerland. 



14. Gerris abbreviaxa. 

 Hydrometra abbreviata, Fabr. Syst. Rhyn. 258. Stal, Hem. Fabr. i. 130. 

 Pyrenees. 



North America. 



15. Gerris aptera. 



aptera, Schum. 



a — d. Illinois. Presented by F. Walker, Esq. 

 e—h. Indiana. Presented by F. Walker, Esq. 



16. Gerris franciscana. 

 franciscana, Stal, Eug. Resa, Hem. 265. 

 California. 



17. Gerris orba. 

 orba, Stal, Eug. Resa, Hem. 264. 

 California. 



18. Gerris robusta. 

 Hygrolrechus robustus, Pack. Amer. Journ. Sci. 1871. 

 California. 



West Indies. 



19. Gerris muiginata. 



marginatus, Guh\ Icon. B. An. Ins. 351, pi. 57, f. 2 ; Sagra, Hist. Cuba, 

 Ins. 415. 



Cuba. 



