No. 22.] HYMENOPTERA OF CONNECTICUT. 6/ 



Thrinax Konow. 



T. impressatus (Provancher). Strongylogaster impressatus 

 Provancher. 



Black, with the following parts rufous ; the tegulse, a triangular 

 spot on the collar, the legs beyond the apices of the coxae, the 

 costa, and the basal third of the stigma, the disk of abdominal 

 segments two, three, and four, wholly or in part, or with the 

 apical half of the first and all of the three following segments ; 

 median fovea large, transverse, ovate ; ©cellar basin indistinct 

 except adjacent to the anterior ocellus. Length 7-10 mm. 



New Haven (B. H. W.). 



Strongylogaster Dahlbom. 

 Key to Species. 



1. Antennas dark rufous, with the basal segments red; body 



black, with the following parts rufous: upper half of orbits, 

 middle of the pleurae, abdomen, and legs in part; with fol- 

 lowing parts yellow: spot between and beneath the anten- 

 nae, lower half of the orbits, labrum, clypeus, collar, scutel- 

 lum, and a spot at the base of coxae; wings infuscated at 



middle. Length 10 mm rufescens 



Antennae entirely black 2 



2. Thorax except collar and tegulae rufous, abdomen rufous 



in female and black in male; remainder of body black; 

 third and fourth segments of antennje subequal; median 

 fovea and ocellar basin wanting; head densely punctate; 



wings strongly infuscated. Length 8 mm unicus 



Thorax either entirely black, or black with collar and teg- 

 ulae pale 3 



3. Abdomen entirely pale beyond first segment 4 



Abdomen entirely or in part black beyond first segment 5 



4. Tegulae and collar black; body and legs black, with abdomen 



and anterior tibiae rufous; wings strongly infuscated; third 

 and fourth segments of antennae subequal; median fovea 

 indistinct; ocellar basin narrow, trough-like; head deeply, 



sparsely punctate. Length 7-8 mm tacitus 



Tegulae and large spot on collar yellow; body black, with 

 abdomen beyond first segment and legs brownish; wings 

 hyaline, costa and stigma in great ' part brownish; third 

 and fourth segments of antennae subequal; head finely, 

 sparsely punctate. Length 9 mm longulus 



5. Abdomen with basal half of each segment straw-yellow and 



apical half black; wings hyaline, stigma and costa pale; 

 antennae v/ith third segment longer than fourth; head 



