No. 34-] HEMIPTERA OF CONNECTICUT I LYGAEIDAE. 711 



largest, and Antillocoris pallidus the smallest, member. From an 

 economic standpoint a few of the Lygaeidae occupy an important 

 position, notably the true and the false chinch bug, Blissus leucop- 

 terus, Nysius ericae, etc. Most of the subfamilies are represented 

 by exclusively plant-feeding species, but the Rhyparochrominae 

 seem to be mainly carnivorous as shown by the character of their 

 fore legs. 



The antennae have four segments, and are inserted on or below 

 the lateral margins of head. Ocelli very seldom absent. Rostrum 

 of four segments. Hemelytra generally coriaceous, consisting of 

 clavus, corium and membrane ; clavus with rare exceptions, form- 

 ing a commissure; membrane with not more than five simple 

 veins. Coxae trochalopodous. Tarsi three segmented ; claws 

 provided with arolia. Nymphs with two or three abdominal 

 odoriferous orifices. Eggs deposited externally. 



This family is divided into seven subfamilies according to the 

 following key : 



Key to Subfamilies. 



1. All sutures between the ventral segments of the abdomen straight 



and reaching lateral margins on each side. Head commonly with- 

 out setae near eyes. Fore femora most commonly unarmed 2 



Suture between the third and fourth ventral segments of the abdo- 

 men curved anteriorly and not reaching lateral margins on each 

 side (except Plinthisus). Head most commonly provided with 

 one or more setae near the. eyes. Fore femora usually swollen 

 and most commonly armed with teeth Rhyparochrominae 



2. All abdominal spiracles situated dorsally. Entire posterior margin 



of pronotum, or at least the margin before the scutellum, turned 

 down convexly. Fore femora not much swollen and rarely armed 



beneath with teeth or spines 3 



All abdominal spiracles not situated dorsally, at least those of the 

 sixth placed on the venter. Posterior margin of pronotum, at 

 least before scutellum, commonly not turned down convexly. 

 Fore femora more or less swollen, armed or unarmed 4 



3. Posterior margin of pronotum between scutellum and lateral angles 



more or less distinctly depressed or impressed. Hemelytra, 

 usually the head, pronotum and scutellum impunctate. Two inte- 

 rior veins of membrane commonly joined together near base by a 



transverse vein Lygaeinae 



Posterior margin of pronotum between the scutellum and lateral 

 angles not distinctly depressed or impressed. Hemelytra, head, 

 pronotum and scutellum distinctly punctate. Two interior veins 

 of membrane not joined together near base by a cross vein . .Cyminae 



4. All abdominal spiracles not situated ventrally, at most only three 



apical ones so placed. Anterior femora moderately incrassate and 



commonly unarmed 5 



All abdominal spiracles situated ventrally. Anterior femora more 

 or less swollen and armed with one or more spines 6 



5. Head always narrower than posterior margin of pronotum; tylus 



not sulcate. Hemelytra not convex and almost if not quite im- 

 punctate ; clavus not narrowing posteriorly, commissure distinct, 

 and at least half as long as scutellum. Fore femora sometimes 



much swollen (Ischnodemus) Blissinae 



Head across eyes very broad, as wide or wider than posterior 



