198 SEVENTEENTH Report STATE ENTOMOLOGIST oF MINNESOTA—1918 
“So far only a single species (of Helorinae) has been detected 
in our tauna.” Ashmead, p. 331, Proc. UW Ss. Nat. Mus) 45,0895: 
Helorus paradoxus Prov. is parasitic on the cocoon of Chrysopa. It 
occurs in Minnesota. The genus Helorus is represented in Europe 
by several species. 
PELECINIDAE 
Trochanters with one joint; antennae with fourteen joints; mandibles without 
teeth; stigma very narrow, long; antennae inserted on middle of face; abdomen of 
female greatly lengthened, about five times the length of head and thorax united, 
composed of six segments; male abdomen clavate. 
The male in this family differs 
strikingly from the female in 
the fact that the abdomen of the 
former is not elongated. 
Pelecinus polyturator Drury, 
occurring in Minnesota, is a 
striking species, the female hav- 
ing a long slender abdomen in 
marked contrast to the short ab- 
domen of the male. The latter 
is rarely seen. The species is 
parasitic on grubs of the May 
Fig. %. NOGA aon Drury, beetle (Lachnosterna), and is 
emale, 
common over most of the tem- 
perate parts of the New World. 
FORMICOIDEA 
A deep constriction at the base of the first abdominal segment conspicuously 
separating the abdomen from the thorax; the first abdominal segment forming a scale 
or knot (petiole). 
All true ants occur 
in this super-family 
and in the single fam- 
ily which alone rep- 
resents the group. 
True ants vareat 
once recognized by 
the presence of one 
or two knots or scales 
at the base of the ab- 
domen. Fig. 85. 
Formica sanguinea Latr. 
