368 PHIL RAU AND NELLIE RAU 



We could see no reason why this spot should be more agreeable 

 to them than any other. Some lime had been thrown over the 

 rocks at this point, but we could not see why this should attract 

 them, since they paid it no heed. Other lime-dumps were near 

 by, which did not attract them. 



Calliopsis nebraskensis Cfd. 



Some little solitary bees, Calliopsis nebraskensis Cfd., often 

 busy themselves upon a bare spot in our field. They live in 

 holes in the ground, and while they are solitary in habit they 

 often exist in communities, i.e., several holes occur near together, 

 but we have not ascertained whether this is because they prefer 

 the community life, or whether merely the desirable features 

 of the sunny bald spot has brought them near to each other. 



These holes are always found closed and covered with a little 

 mound of loose, well-pulverized earth. Not infrequently one 

 sees this loose soil move, but evidently the occupant of the 

 hole is only pushing up more dirt from below. Only rarely 

 does one see her come tumbling out through the top of the 

 mound, gather herself together and shake off the dust all in 

 an instant, while the loose dirt again closes behind her, and 

 dart off on the wing. It is a wise precaution that she keeps 

 her nest always covered, for I have seen vandals prowling about 

 these homes more often than I have seen the rightful owners. 

 In fact, I long thought that these burrows and mounds actually 

 belonged to certain tiny black-and-red wasps, who make very 

 bold in the liberties they take about them. 2 



Now these little bees have one strange antic which has aroused 

 our curiosity a number of times. First, one's* attention is at- 

 tracted to some little object buzzing around on the dusty ground, 

 in the manner of an insect which has fallen upon its back and is 

 struggling to get on its feet. It is a pair of these little bees, 

 clasping each other by the legs, ventral to ventral, and with 

 their bodies curved, so that the two united form almost a ring. 

 Thus they continue buzzing and spinning and tumbling about 

 on the dusty ground, whirling 'round and 'round in small circles 

 near the same spot. In its intensity the struggle has much the 

 appearances of a miniature dog-fight. I have never been so 



'■ This was later identified as the parasitic bee Specodes sp. by Mr. S. A. Rohwer. 



