712 CONNECTICUT GEOL. AND NAT. HIST. SURVEY. [BuU. 



margin of the pronotum. Tylus usually sulcate Hemelytra 

 convex and plainly punctate; clavus commonly narrowing pos- 

 teriorly ; commissure usually absent or very short. Fore femora 



moderately incrassate and unarmed Geocorinae 



6. Anterior femora much swollen and armed with numerous teeth. 

 Exterior vein of corium not parallel with costal margin. Corium 

 not wider than abdomen. Bucculae short, confined to front of 



head. Posterior coxae not widely separated Pachygronthinae 



Anterior femora only moderately swollen and armed with a single 

 tooth. Corium expanded, wider than abdomen; exterior vein 

 sub-parallel with margin of corium. Bucculae extended through 

 the head. Antennae inserted close to bucculae. Posterior coxae 

 widely separated Oxycareninae 



■ Subfamily Lygaeinae Stal. 



Key to Tribes and Genera. 



1. Apical margin of coritun straight, not sinuate inwardly. Exterior 



apical angle of antenniferous tubercles obtuse or sub-obtuse. 

 Last dorsal segment of male truncate. Genital segment of male 



not f oveate ( Tribe Lygaeini) 2 



Apical margin of corium inwardly sinuate. Apical angle of anten- 

 niferous tubercles prominent, acute or sub-acute. Sixth dorsal 

 segment of male rounded. Genital segment of male foveate 

 (Tribe Orsillini) 3 



2. Posterior margin of pronotum before scutellum sinuate; carinate 



anteriorly in the middle. Scutellum more or less tumid and 

 carinate apically Oncopeltus, p. 712 



Posterior margin of pronotum truncate ; without a. median keel or 

 with keel not reaching anterior margin. Scutellum not tumid; 

 with a longitudinal keel, commonly joined to a transverse keel at 



base Lygaeus, p. 713 



.3. Basal segment of antennae surpassing apex of tylus. Head mod- 

 erately elongate. Rostrum short, its apex scarcely reaching upon 

 abdomen 4 



Basal segment of antennae not reaching apex of tylus. Head 

 much elongated. Rostrum long, reaching beyond middle of venter 



Belonochilus, p. 715 

 4. Costal margins of hemelytra straight throughout, parallel or con- 

 verging posteriorly. Eyes prominent; exposed area back of eyes 

 greater than half of width of eyes. Bucculae less than half the 

 length of gular area. Apex of orifices exteriorly, prominently 

 auriculate Ortholomus, p. 714 



Costal margins of hemelytra straight only at base, if at all. Eyes 

 not so prominent. Bucculae variable. Apex of orifices suddenly 

 i abbreviated, rarely sub-auriculate Nysius, p. 714 



f Tribe LYGAEINI. 



Oncopeltus Stal. 



O. fasciatus (Dallas). 



List of Hemip., ii, 538, 1852. 



The largest and showiest member of the family occurring in 

 New England. Measures fully 15 mm. to tip of membrane. The 

 hemelytra, lateral margins of pronotum and a Y-shaped mark on 



