isely: eumenid^ of kansas. 283 



river, was mature. When I found it some of the wasps were 

 emerging from their larval cells. I had no way of telling 

 whether these nests were excavated earlier in the year, or 

 whether they had been built the year before and the emerging 

 wasps had wintered there. Throughout the month of July I 

 had found 0. dorsalis quite common about the watering places, 

 but found no sign of nest building. 



The nests of 0. do7'salis found along roads or in open spaces 

 in pastures, were, as I have stated, burrows, vertical or nearly 

 so, at the bottom of which the larval cells were located, one 

 above the other. The depth of the burrow to the bottom of the 

 cells was sometimes four inches; the depth above the highest 

 cell varied from three-fourths of an inch to two inches. The 

 diameter of the burrow was one-fourth inch. 



In three-fourths of the nests that I opened were two cells; 

 the remainder of the nests had only one cell. The cells were 

 always one below the other in the direct line of the burrow, 

 never at one side. 



In form the cell varied from globular to barrel-shaped. In 

 size there was also considerable variation. Cells excavated in 

 the same locality, in the same kind of soil and under the same 

 conditions showed noticeable variations both in shape and size. 

 Sometimes cells in the same nest differed markedly from each 

 other. The extent of this variation may be shown by a com- 

 parison of measurements of cells of four nests located in open 

 spaces in a pasture within seventy-five feet of each other. The 

 descriptions of these cells as given in my notes are as follows: 



Nest 1. — Two cells; globular. Cell 1 — vertical diameter, ^"ie 

 in. ; horizontal diameter, same. Cell 2 — vertical diameter, 'He 

 in. ; horizontal diameter, ^%; in. 



Nest 2. — One cell ; globular. Vertical diameter, '"ie in. ; 

 horizontal diameter, "/io in. 



Nest 3. — Two cells; barrel-shaped. Cell 1 — vertical diame- 

 ter, ma in. ; horizontal diameter, 1/2 in. 



Nest 4. — One cell ; barrel-shaped. Vertical diameter, % in. ; 

 horizontal diameter, 1/2 in. 



No tube was built over the entrance of this burrow, as is the 

 case with so many of this genus, but the earth excavated was 

 not left about the nest. The pellets are dropped in piles from 

 e'ghteen inches to two feet from the entrance. 



When the nest was stored with caterpillars, O. dorsalis did 

 not stuff the burrow with earth. She simply closed the cell, 



