The Sphegoidea of Nebraska 51 
Family LARRIDAE 
KEY TO THE SUBFAMILIES 
Hind ocelli normal, distinct. 
Second cubital cell petiolate or triangular, or more rarely entirely want- 
ing; pronotum most frequently short, transverse........ PISONINAE 
Second cubital cell never petiolate, receiving both recurrent nervures, 
or the first and second cubital cells each receive a recurrent nervure; 
SeasUIAREANEET NOR ONs Iaann, aehaysn oinksi dee ooce eo oS a'els dieiclepaiely ames ae LYRODINAE 
Hind ocelli more or less distorted, obsolete or subobsolete; mandibles most 
frequently emarginate on under side .............0.000. LARRINAE 
Subfamily PISONINAE 
Genus Plenoculus Fox 
SYNOPSIS OF THE SPECIES 
Mandibles reddish medially; hind tibiae and tarsi not at all yellow- 
“EL SUSIE Se et tpt OR eae es Pa ae ee propinquus 
Mandibles, and hind tibiae and tarsi more or less, yellowish....... davisit 
Plenoculus propinquus Fox. 
s 1893. Plenoculus propinquus Fox, Proceedings of the Academy of 
Natural Sciences of Philadelphia, p. 536. 
A single female taken at Glen, Sioux county, August 20, 1906 
(H. S. Smith). This and the following are small black wasps, 
from four to six mm. in length. 
Plenoculus davisii Fox. 
1893. Plenoculus davisii Fox, Psyche, vi, p. 544. 
1893. Plenoculus davisii Fox, Proceedings of the Academy of Natural 
Sciences of Philadelphia, p. 536. 
Two females, West Point, June (L. Bruner). 
Subfamily LYRODINAE 
Genus Lyroda Say 
SYNOPSIS OF THE SPECIES 
Size large, 14-15 mm.; wings dark smoky; form stout, opaque black, 
abdomen without silvery pile; anterior margin of clypeus of fe- 
Maleunotratealle dentate lateralliveracmc.u): 126 lee seinen aeeoe ene triloba 
Size smaller, 7-13 mm.; wings hyaline, tips dusky; more slender than 
the above, and with silvery pile on the abdomen; anterior margin 
of clypeus of female armed with three distinct teeth laterally. .subita 
373 
