No. 22.] HYMENOPTERA OF CONNECTICUT. 121 



2. Ocellar basin with indistinct lateral walls and without tuber- 

 cles; clypeus nearly truncate; frontal crest large and 

 rounded; saw-guides thick, short, scarcely projecting, 

 margined with long, not very numerous curved hairs; body 

 yellowish ferruginous, with antennae, spot on either side of 

 scutellum, metathorax in part, basal plates, and center of 

 abdomen above, black; mesonotum, pleurae in part, margin 

 of abdomen, and sheath, more or less reddish. Length 5 mm. 



chloreus 



Ocellar basin with distinct lateral walls and containing two 

 small tubercles; clypeus broadly emarginate; frontal crest 

 large, obtusely rounded; saw-guides thick, squarely trun- 

 cate, tubular; body luteous, pallid or reddish yellow, with 

 the sides of the mesonotum, most of the metanotum, and a 

 broad stripe on the middle of the abdomen, black. Length 

 7 mm pergandei 



N. unicolor Marlatt. Larva feeds on birch. 



*N. chloreus Norton. Larva feeds on Quercus coccinea. 

 Connecticut (E. N.). 



N. pergandei Marlatt. 



Croesus Leach. 



C. latitarsus Norton. PI. i, Figr. i. 



Mesothorax with confluent longitudinal punctures; body 

 blue-black, with the labrum, mandibles, palpi and the anterior 

 pair of legs toward the tip, piceous ; posterior trochanters and 

 the basal half of all the tibise white ; wings hyaline, with a smoky 

 area beneath the stigma. Length 8 mm. Larva feeds on birch. 



New Haven, 1910 (B. H. W.) ; Stafford, 24 August, 1906 

 (W. E- B.). Common in New Haven. 

 C. laticulus Norton. 



Mesothorax with scattered, sub-obsolete, oval punctures ; body 

 black, with tegulse, and a spot on the sides of the basal plates 

 and of the second and third abdominal segments, whitish ; 

 mandibles at apex, and legs, ferruginous, with apical two- 

 thirds of their tibiae and greater part of metatarsi black; wings 

 hyaline. Length 12 mm. 



Amauronematus Konow. 

 Key to Species. 



I. Body black on dorsum 2 



Body pale on dorsum, marked more or less with black 9 



