120 Bulletin Wisconsin Natural History Society. [Vol. 8, No. 3. 



Oxyoelis : Builds a beautiful nest, in which the g-allery penetrates 

 in an inclined way, with sides nicely smoothed. The end of the gallery 

 is made into the first cell, closed up. and one or more further cells 

 made in this manner. The wasp then proceeds to make lateral gal- 

 leries and stores them similarly. Flies exclusively are used by this 

 wasp for prey. 



Astata unicolor and bicolor: Seem to prefer ground to sand. In 

 the nests found the first inch was tubular and then an area varying 

 from two to three inches of loose earth was encountered, which was 

 thoroughly permeated by the plaster in the pouring. The central por- 

 tion of this loose earth was tubular, contained no cells, penetrating 

 iu a rather tortuous manner to a depth of from S to 14 inches. In 

 these nests the prey was found to be a flat bug, which was placed 

 transversely in the bottom of the cell. 



Bcmbex and Micro oemb ex : These present some evidence of the 

 social instinct, as nests are found more or less in groups or colonies. 

 The wasps heretofore mentioned close their nests upon leaving. Those 

 following were not observed to do so. Iiembex and Microberribex are 

 probably a little higher in the scale inasmuch as the larva are fed 

 from day to day. the nest remaining open during the excursions. This 

 would probably account for the fact that the young are frequently 

 found parasitized. When the larva is ready to spin its cocoon the cell 

 is closed up and the nest completed. 



The nest of Bembex usually has a tubular gallery some five or six 

 inches in length in the sand, and forms a wide curve to the larval 

 chamber at the bottom. 



Crabronid<e : Wasps of this family may be divided into ground, 

 pith and wood borers. The ground borers (Crabo lentils and errans) 

 construct a nest very similar to that of Oxybelis, and store with ilies 

 and bugs. The pith borers excavate the pith of the stem in a straight 

 tube and then store a series of cells, separating each by a varying 

 depth of chewed pith. No lateral galleries are formed. Nest usually 

 occupies major portion of the pithed cavity of the stem. The wood 

 borers frequently utilize an old beetle burrow and from the bottom or 

 the end of this continue excavations or begin the nest de novo. Usually 

 quite complicated, the galleries proceeding in all directions with vary- 

 ing Groups of cells, until frequently the entire soft portion of the wood 

 is utilized, the cells again being separated by a varying depth of saw- 

 dust. 



