456 NORTH AMERICAN INDEX FOSSILS. 



About 19,000 living and 450 Tertiary species are known, 150 of 

 these being from North America; the order begins in the Lias. 

 The capsids or soft bugs (Capsidcu), are represented by about 14 

 species at Florissant (Carmelus gravatus Scudder, Closterocoris 

 elegans Scudder, Capsus obsolef actus Scudder, etc.) ; the Redu- 

 viidcB by several species (Eothes elegans Scudder, etc.) ; the water 

 bugs (Hydrometridce) by Stenovelia nigra Scudder, and others; 

 the Lygceidce, or long bugs (chinch bugs, etc.), by about 60 species, 



Fig. 1763. Planocephalus aselloides, dorsal, lateral and sectional view of a 

 restoration, X 3- (After Scudder. ) 



at Florissant (Lygaeus obsolescens Scudder, Trapezonotus exter- 

 minatus Scudder, Linnaea evoluta Scudder, Lithocromus gardneri 



Scudder, etc.), and others, in the White River beds of Colorado. 

 The Coreid(2 (squash-bugs, etc.) are represented by about a dozen 

 species at Florissant (Heeria gulosa Scudder, H. lapidosa Scudder, 

 etc.) ; the Tingitidce only by a few (Eotingis antennata Scudder) ; 

 the Pentatomidce are found at Florissant (Procydnus divexus Scud- 

 der, and six other species, Thlibomenus six species, Necrocydnus 

 seven species, etc.) ; and in the Green River beds of Wyoming 

 (Procydnus mamillanus Scudder, etc.). The Corixidce finally are 

 represented by Corixa immersa Scudder, and other species at Floris- 

 sant. Here also has been placed the remarkable Planocephalus 

 aselloides Scudder (Fig. 1763), originally placed by Scudder among 

 the Thysanura but regarded by Handlirsch as the larva of an 

 Hemipterous insect. 



Order HOMOPTERA Leach. 

 {Plant lice, wax-hugs, harvest-flies, etc.) 

 Front of the head much inflexed, so as to be in contact with the 

 coxae, scarcely movable ; wings similar, front wings seldom denser 

 and more coriaceous than hind wings ; anal field well developed, 

 with four veins or less, sometimes rudimentary or wanting; C 

 marginal; Sc and R often united; M and Cu free; branching of 

 longitudinal veins very variable; cross-veins seldom numerous. 



