656 
THE STUDY OF INSECTS. 
A very common species in the East is Stigmus frater 7 ius 
(Stig'mus fra-ter'nus). This insect measures one fifth of an 
inch or less in length, and makes very tortuous burrows in 
the pith of sumach (Fig. 782). Other common members of 
the family are larger. 
Family CRABRONIDS (Cra-bron'i-dae). 
The Crabronids (Cra!bro-nids). 
The Crabronids can be distinguished from all other digger 
Fig. 783.—Wings of Cralo singularis. 
wasps that occur in this country by the vena¬ 
tion of the fore wings, in which there is only 
one closed submarginal cell (Fig. 783, 
2d III-f-III 5 ). The head is gener¬ 
ally large, and nearly square when 
viewed from above, and sometimes 
f g broader than the thotax (Fig. 784). 
c'rabro. The different members of this 
family vary greatly in their nesting habits. 
Some mine in the pith of such plants as sumach 
and elder; some bore in more solid wood; 
some dig burrows in the ground ; and others 
make use of any suitable hole they can find, 
often the deserted burrow of some other in¬ 
sect. These insects usually provision their nests 
with flies; but we have found spiders in the 
nests of some. 
Fig. 785.— Nest of 
Trypoxylon fri- 
gidum . 
