Il6 CONNECTICUT GEOL. AND NAT. HIST. SURVEY. [Bull. 



raised, slightly broken at middle; antennae with third seg- 

 ment much shorter than fourth; saw-guides long, rounded 

 at apex, blades thin and closely applied; body brownish 

 black, with abdomen lighter, inclined to fulvous; face below 

 antennae, the upper and posterior orbits, pronotum, tegulae, 

 and legs except bases of coxae, reddish yellow, strongly in- 



f uscated. Length 8 mm dimmockii 



Body in great part yellow or resinous; ocellar basin with 

 distinct and broad lateral walls; frontal crest strong and 

 unbroken; antennal segments three and four subequal; 

 saw-guides long and large, broadly rounded at apex, 

 blades thin, translucent, closely applied; body shining 

 resinous yellow, with antennae, spot on lateral lobes of 

 mesonotum, apex of scutellum, metanotum in part, and 

 narrow border to basal plates, brownish black. Length 

 8.5 mm ocreatus 



4. Head strongly developed and dilated behind compound eyes 5 

 Head narrowed more or less behind compound eyes 10 



5. Head and mesonotum in great part pale 6 



Head black, with orbits black or strongly infuscated; thorax 



in great part black 9 



6. Ocellar basin with strong, distinctly defined sides; frontal crest 



strong, very minutely notched; median fovea extending 

 laterally over bases of antennae; saw-guides moderately 

 broad and thick, obliquely truncate, upper edge nearly 

 straight; body resinous or sulphur yellow, with antennae, a 

 small spot including the ocelli, spot on lobes of mesonotum, 

 spot on either side and base of scutellum, metanotum, 

 tergum of abdomen except narrow lateral margin and two 

 terminal segments, and saw-guides, brownish black. Length 



7-8.5 mm extensicornis 



Ocellar basin with its sides and the frontal crest indistinct 7 



7. Wings hyaline ; median fovea distinct 8 



Wings infuscated; median fovea almost wanting; saw-guides 



narrow and pointed at tip, upper edge straight; body shin- 

 ing honey-yellow, with antennae, a spot about the ocelli, spot on 

 lobes of mesonotum, apex of scutellum, metanotum, cen- 

 ter of basal plates, and bases of first six dorsal abdominal 

 segments, black or fuscous. Length 6.5 mm suadus 



8. Median fovea shallow, and extending widely over bases of 



antennae; antennae with fourth segment as long as or 

 longer than third; saw-guides narrow, tapering, straight on 

 upper margins, obtusely pointed ; body luteous, with an- 

 tennae, a small spot including the ocelli, a spot on lateral lobes 

 of mesonotum, scutellum in part, metanotum in part, 

 basal plates, disk of tergum, and saw-guides, black; apices 



