38 Some Solitary Wasps op Texas. 
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 Bembecid 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 Microbembex closes up 
her nest from the outside and sleeps elsewhere, while occasionally a 
Bembex 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 Microbembex more closely and leave a detailed de- 
scription of Bembex t exanus for a time, when I shall have collected 
more data on this interesting wasp. 
Microbembex 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 1 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 , 1 % 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- 
turns, to search for her prey, she does so by flying slowly round and 
round in the vicinity of the caterpillar. 
These tactics expose the prey to considerable danger from para- 
