22 Some Solitary Wasps of Texas. 



sand pours out from under the wasp, propelled by several smart 

 strokes of the front legs in quick succession. Then there will fol- 

 low a brief pause while the wasp rests with head in air as if look- 

 ing around an instant to survey the landscape. 



Activities in one of these Bejnbecid colonies does not begin until 

 the rays of the sum have warmed the ground ; and when the rays 

 beat down from above, business is at its height and a gentle hum 

 betokens the hustle and bustle of the inhabitants. When one visits 

 the colony early in the forenoon, when scarcely a wasp is about, com- 

 paratively few of the nests are visible, since' Microhenfb ex closes up 

 her nest from the outside and sleeps elsewhere, while occasionally a 

 Bemhcx Tex. will have her nest closed from the inside. Towards 

 ten o'clock, however, the doors are thrown open, one by one, and 

 soon the actual population of the colony is manifested. On cloudy 

 days, the wasps are not as busy, but lounge about, often resting for 

 hours at the entrance and looking out upon the world. 



Having thus located ourselves in the midst of this mixed colony, 

 I shall follow Microhemhex more closely and leave a detailed de- 

 scription of Bembex texanus for a time, when I shall have collected 

 more data on this interesting wasp. 



Microbemhex is unique among the solitary wasps in the variety 

 of the insects with which it feeds its larval offspring. Bembex takes 

 several species of flies, but never anything but flies; similarly, a 

 bug-catcher takes only bugs and a spider-ravisher only spiders. The 

 greatest variety of the prey of the solitary wasps of which I can 

 find any record is Monedula punctata described by Bates, who says 

 that this species catches fire-beetles as well as flies. Our Micro- 

 bembex will take home for provisioning its nest and insects that it 

 finds already dead, or it will capture the living prey. On account 

 of this great variety of food, I shall give a detailed list of the ar- 

 ticles of food together with notes on the behavior of the wasps in 

 capturing or in carrying home the prey. 



" (1) Slender red caterpillars, li^ inches long. I saw five of 

 these carried home by different individuals. The caterpillar is 

 carried home on the wing, though not directly, because of the weight 

 of the burden, but in spurts. The wasp grasps her prey by its 

 head with her mandibles and flies suddenly in a kind of jump to 

 another point, one to three feet away, where she lays the cater- 

 pillar down and rests. Sometimes the wasp will fly off for a 

 moment , leaving the caterpillar lying in the sand. When she re- 



