1915] Parshley — Systematic Papers on New England Hemiptera 91 



11. Antenna; 5-segmented 12 



Antennae -l-segmented, disregarding minute ring-segments; (antenniferous 



tubercles of head should not be mistaken for segments, figs. 11, 30) 13 



12. First and second segments of antennae thicker than the others (fig. 8); clavus 



similar in texture to the membrane which is without veins (fig. 22) ; head and 

 thorax sulcate beneath; rostrum 3-segmentcd; tarsi 2-segmented; aquatic, 



living on the surface; minute in size HEBRIDiE or NiEOGEID-S 



First segment of the antennae thickened, second slender (fig. 1); margin of head 

 carinate above insertion of antennae; scutellum rather large, usually extend- 

 ing beyond middle of abdomen; terrestrial; moderate in size, rarely minute 32 



13. Frosternum with a median longitudinal transversely striated or granulated 



stridulatory groove visible anterior to front coxae, I'eceiving the tip of the 

 rostrum; rostrum 3-segmented, short and strong; length not less than 5 



mm ■ 14 



Frosternum without a stridulatory groove; size large or small 15 



14. Terminal segment of antennae thickened; front legs highly modified, stout, 



raptorial (fig. 13); scutellum moderate in size; membrane with numerous 

 veins; front tarsi small and retractile; tarsi 2-segmented; roughly sculptured 

 predatory forms; moderate in size PHYMATIDiE or MACROCEPHALID.S 

 Terminal segment of antennae filiform (sometimes faintly divided into numer- 

 ous small parts); front legs usually much like the others, though raptorial 

 in function, sometimes somewhat thickened and spinous; scutellum small; 

 membrane with few veins; tarsi 3-segmented; body robust or linear; usually 

 predatory; large or small in size REDUVIID.^ 



15. Hemielytra closely reticulate in relief, membranous between the reticulations, 



more or less lace-like in appearance (figs. 17, 18) ; size small 16 



Hemielytra not so reticulate, or absent; size large or small 17 



16. Juga free, produced before apex of head, longer than tylus (fig. 14) ; hemielytra 



with a non-reticulate membrane, the rest reticulately punctate (fig. 18); 

 ocelli present; rostrum 4-segmented; tarsi 2-segmented; one small species 



PIESMID-(E 



Juga not prominent, not longer than the tylus (fig. 15), head sometimes with 



dorsal anteriorly projecting spines; hemielytra of similar texture throughout, 



densely reticulate (fig. 17), membranous between the reticulations; ocelli 



absent; rostrum 4-segmented; tarsi 2-segmented; numerous small species 



TINGITID.S 



17. Fronotum divided into three lobes; head contracted behind the eyes; hemi- 



elytra wholly membranous, with a few distinct longitudinal and cross veins; 

 ocelli present; rostrum 3- or 4-segmented (?); front tarsi 1-segmented, 

 intermediate and hind 2-segmented; predatory; fly in swarms; very minute 



and delicate forms' *HENICOCEPHALID^ 



Fronotum, head, and hemielytra otherwise constructed 18 



18. Rostrum really or apparently 3-segmented 19 



Rostrum 4-segmented, first segment sometimes short (fig. 11) 24 



For figures see Johannsen, Psyche, XVI, 1909, pi. i. 



