130 CONNECTICUT GEOL. AND NAT. HIST. SURVEY. [Bull. 



abdomen on dorsum except narrow lateral margin, and apex 

 of saw-guides, black; scutellum at base, and suture of 



mesonotum, inclined to reddish. Length 5.5 mm odorata 



Head triangular in outline when viewed laterally; clypeus 

 broadly, circularly emarginate, lobes rounded, not broad; 

 ocellar basin deeply and distinctly excavated, lateral walls 

 rounded ; frontal crest strongly developed, divided by a 

 narrow depressed line at middle; median fovea deep; saw- 

 guides narrow, tapering to a rounded tip ; body pallid or resin- 

 ous, with antennae, large spot covering vertex, dorsum of 

 thorax, and abdomen except narrow lateral margin, black ; hind 

 tarsi and saw-guides brown ; hind tibiae darker at tip. Length 

 7 mm comelli 



27. Posterior tibiae and tarsi dark brown; ocellar basin with 



distinctly defined sides; frontal crest distinct, unbroken, 

 curving anteriorly; median fovea triangular, sharply de- 

 fined; saw-guides narrow, smooth, tapering on both edges 

 to rounded tip; body reddish yellow, with antennae, large 

 spot on vertex extending onto occiput, mesonotum, small spot 

 beneath anterior wings, metanotum except postscutellum and 

 sutures and lateral margin, abdomen except lateral margin and 

 apical segment, apical half of saw-guides, and posterior tibiae 



and tarsi, brownish black. Length 6.5-7 ni™ trilineata 



Posterior tibiae and tarsi resinous; ocellar basin distinctly 

 defined, sides faintly raised; frontal crest stout; median 

 fovea elongate, rather deeply excavated; saw-guides broad, 

 obtusely pointed, densely hairy at apex and on lower margin ; 

 body yellow ferruginous, with the antennae basally, spot on 

 the head surrounding the ocelli and extending narrowly over 

 the vertex, large spot on anterior lobe of mesonotum, apex of 

 scutellum, metanotum, and abdomen on dorsum except narrow 

 lateral margin and more or less of some of the middle seg- 

 ments at apex, black. Length 8 mm magna 



28. Frontal crest broad, unbroken at middle 29 



Frontal crest broad, broken at middle 30 



29. Antennae with third segment longer than fourth; saw-guides 



robust, densely clothed with long, whitish hairs at apex 

 on lower margin; clypeus nearly truncate; ocellar basin 

 indistinctly defined, sides rounded; frontal crest broad, 

 unbroken; median fovea defined only on anterior margin; 

 body yellowish or ferruginous, with a spot on the vertex ex- 

 tending back over the occiput, mesonotum, metanotum, and 

 dorsum of abdomen except a narrow lateral margin, black. 



Length 4.5 mm quercus 



Antennas with third segment shorter than fourth; saw-guides 

 narrow, tapering to a rounded tip; clypeus very broadly 

 but not deeply emarginate; ocellar basin with distinctly 



