1918] Barber — Synoptic Keys to the Lygceidoe {Hemiptera) 79 



BB. Anterior lobe of pronotum three or four times as long as 

 posterior lobe, with the transverse constriction between the 

 lobes commonly shallow and obtuse or ill-defined. Head 

 distinctly exserted; postocular space subequal to space 

 between antenna and eye; most commonly not abruptly 

 contracted back of eyes. Fore tibia of males provided 

 with a submedian tooth. Antenna elongate; apex of head 

 not attaining middle of basal segment; this segment sub- 

 equal to basal segment of rostrum. Basal segment of pos- 

 terior tarsus two or three times as long as second and third 

 segments together. Membrane not entirely wanting in 

 brachypterous forms. 



M. Anterior lobe of pronotum impunctate, de- 

 marked from the posterior lobe by a transverse, 

 impressed line; provided with a distinct ring- 

 like collar. Basal segment of antenna with a 

 few setose bristles. Ocelli absent. Fore tibial 

 tooth of male at middle or posterior to the 

 middle. Hind tibia provided inwardly and 

 outwardly with rigid bristles. Basal segment 

 of hind tarsus three times as long as second 

 and third together.. Larger species. 



Cnemodus H. S. 

 MM. Anterior lobe of pronotum sparsely punctate, 

 the two lobes separated by an obtuse sinus, 

 not indicated by an impressed line; anterior 

 margin depressed, punctate. Basal segment 

 of antenna without setose bristles. Ocelli 

 present. Fore tibial tooth of male anterior to 

 middle. Hind tibia with a few setose bristles 

 inwardly. Basal segment of posterior tarsus 

 about twice the length of second and third 

 together. Smaller species. (Type — P. cana- 

 densis Prov.) Pseudocnemodus Barb. 



Tribe Rhyparochromini. 



A. Anterior margin of the pronotum provided with a distinct 

 ring-like coHar, behind which is a depressed series of punc- 

 tures; lateral margins strongly keeled or lightly expanded 



