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ceeded to blunder off, but just then, and in some excitement, the 
huntress emerged and, quickly finding the hurrying cricket, 
pounced upon it and administered one or more quieting stings, 
apparently on the underside of the thorax. Then, after chewing 
at her prey for a brief period, she mounted crosswise upon the 
thorax and, bending her abdomen under the latter for a few sec- 
onds, laid an egg. By this time Solenopsis ants, ubiquitous 
and unpleasant insects of the lowlands, had discovered the 
paralyzed cricket; Larra resented the presence of these for- 
agers by making short dashes and gingerly bites at them. But 
they became numerous and _ bold and would not be driven off. 
Much to my surprise, the cricket, after receiving several good 
nips and stings from these ants, awakened and hastily made 
off, her wasp captor now showing no further concern. Evi- 
dently the cricket is paralyzed just about long enough for the 
wasp to lay her egg upon it, and this she does so that it will not 
be bitten nor rubbed off as the mole cricket plows its way through 
the soil. The egg is strongly secured crosswise to fit into the 
deep inter-segmental incision of the underside of the first and 
second divisions of the thorax, its curvature corresponding with 
that of its bed. It is whitish, somewhat polished, slightly thicker 
and more broadly rounded at one end, and seemed to be about 
1.5 mm. long. The cricket itself was 14 mm. long, somewhat 
larger than the Larra, and provided with short wing-pads. 
Thus we have a rather curious condition here—a wasp, be- 
longing to a group which digs nest burrows and provisions them 
with more or less paralyzed prey which are imprisoned in cells, 
adopting the habit of leaving her prey, momentarily immobilized, 
at large, but minimizing the ‘perils of her progeny by securing the 
egg more efficiently than do her sisters. Probably some others 
of the genus Larra act similarly. 
The mole-cricket, which I now captured, seemed as active and 
strong as ever and burrowed rapidly into the earth of the 
tumbler provided it. 
The egg hatched in about four days, when it seemed to have 
split longitudinally, but, the shell, being so thin, as in most of 
the sphecid wasps, 1t was hard to distinguish and decide just 
when the larva began to be freed therefrom. On August 6, two 
days after hatching, the eggshell could be made out on the 
underside and posterior end. of the wasp grub, the latter having 
considerably increased in size and gradué iIly encircling the cricket. 
On the morning of August 7 the strongly- -curved wasp larva, quite 
firm and well segmented, encircled three-fourths of the thorax of 
the cricket, w hich, though still digging, was evidently losing some 
of its vigor. The larva’s head appeared inserted into the back 

