300 WASP STUDIES AFIELD 



FIG. 54. The turret over the burrow of Odynerus geminus. Twice 

 natural size. 



about one- fourth inch in diameter and two inches in total 

 length. It goes straight downward for half its length, 

 then turns abruptly, usually forming an angle of approxi- 

 mately 60 with the perpendicular, although occasionally 

 this angle approaches a right angle. The end of this channel 

 is very slightly wider than the upper portion, and forms one 

 of the "pockets" which make up the nest (see fig. 55). 

 Other channels, with a similar pocket, may branch off from 

 the main burrow at the point of the sharp bend. We 

 have found from one to four pockets to a single nest, but 

 we do not know whether the wasps vary so in their habits 

 of nest-building, or whether the smaller nests were only in- 

 complete. We suspect that the construction of a single 

 cluster of cells extends over a considerable length of time, 

 because, in one nest of four pockets which we excavated, 

 one cell contained a larva of considerable size, while the 

 others contained smaller larvae or egg and caterpillars. 



Hungerf ord and Williams 1 find no mud tubes over the tun- 

 nels of 0. geminus, and a part if not all of the pellets of 

 earth are deposited within two or three inches of the en- 

 trance to the hole. We find that 0. geminus drops her 

 iEnt. News 23: 253. 1912. 



