THE BEMBICENE WASPS 25 



the hard-packed earth with her jaws to obtain the neces- 

 sary filling. 



The same morning another Bembix alighted upon a par- 

 ticular spot which to us was absolutely indistinguishable 

 from all the rest of the smooth-washed "diamond." She fell 

 industriously to digging, and in a moment opened her tun- 

 nel and entered. She had evidently been away from home 

 during the storm and found shelter elsewhere. Even this 

 new condition of the soil about the nest did not confuse 

 her. Some minutes later, upon returning, we were surprised 

 to see the hole again covered, and the topography smooth, 

 but about six inches from the hole (the place was marked 

 or it would have been quite indistinguishable) was much 

 loose dirt which had been swept well away from her door. 

 On one occasion of exceptionally heavy rains the earth from 

 the upper side of the area washed down and deeply covered 

 every trace of their nests; but before evening about a dozen 

 had worked their way out of their holes, none the worse 

 for wet weather. 



It was on July 2 of the first year of our observations, 

 or just two weeks after the first emergence and dance of 

 Bembix, that we dug out the first nest that was completed 

 and occupied. The waspling- was only a tiny larva one- 

 fourth inch long, and was feeding upon its first fly, a deli- 

 cate little yellow-winged Dipteron. On many occasions 

 thereafter, when we found a very tiny larva feeding, the 

 prey invariably was a very soft, delicate little yellow- or 

 green-winged fly not the coarse, heavy kind such as house- 

 flies, stable-flies or horse-flies, which the mothers bring in 

 when the larva is stronger. Can human intelligence do 

 better in delicate, maternal care? It was startling at first 

 to see a tiny larva and fly fairly "rattling around" in so 

 large a cavity; but it only proves again the maternal solici- 

 tude of Mother Bembix who, it seems, knows how to esti- 



