THE STUDY OF INSECTS. 



A very common species in the East is Stigmus fraternus 

 (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 CkABRONlDyE (Cra-bron'i-dae). 



The Crabronids (Cra' bro-nids). 

 The Crabronids can be distinguished from all other digger 



FIG. 783. Wings of Crafa singular!*. 



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 

 broader than the thorax (Fig. 784). 



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 



, fllkU-IPUi' 



with flies; but we have found spiders in the FlG . 78s ._ Nest O t 



. Trypoxylonfri- 



nests of some. 



