116 
of the cage as her private property and dart down upon a 
passer-by. 
Such affairs may happen frequently of an afternoon, and in 
consequence greatly reduce the number of roaches parasitized. 
The fights among the wasps are very fierce and often last many 
seconds. Of course, their movements are rapid, but the little 
wasps are stiff in their heavy armor; they do not fight face to 
face, but endeavor to curl about each other’s middle, their heads 
often or usually free of each other, their stings likewise. They 
fight in a sort of jerky manner—with their legs it would appear— 
perhaps using their stout and no doubt powerful coxae and 
femora. At any rate, permanently disjointed wings or legs some- 
times result, and a weakened insect may be attacked again so that 
it eventually dies. 
Seldom does a dolichurid attack a mature Blatella; these are 
too swift and powerful. I saw one of these wasps being dragged 
rapidly over the ground and under a clod by one of these roaches, 
which finally freed itself of the unwelcome companion. 
The egg of Dolichurus is pearly white, slightly curved and 
rather slender. It is deposited for its length: along the outer 
face of one of the middle coxae, its blunter and broader end 
nearer the base of the latter, (Fig. 55). The roach which bears it 
has usually lost the greater eee of its antennae, and becomes 
moderately active, without regaining the power of making a long- 
sustained or rapid run. One such insect which I kept in a small 
vial had a decided appetite and ate pineapple, etc., until weak- 
ened by the larva. The egg hatches in a little over thirty hours, 
the head being at the blunter end, which lies near the base of 
the leg and where there is a convenient soft area whereon the 
larva may commence feeding. 
The following is a life-history table: 
eau 
emerged 

July 10, 11:40 a. m. 
July 11, 3:00p.m. 
Sept. 12, 4:15 p.m. 
July 1157 925 pam.s| Jiulivs WoO 00%as mie) Atos el 
July 12, 7:15p.m./ July 16,7:00p.m. | Aug. 2 
| 
Egg laid Egg hatched | Cocoon formed 
| Sept. 14, 10:00 a.m. | Sept. 19,6:00 a. m. 
It is seen from the above that the life history for a fossorial 
wasp is remarkably brief, though doubtless during the cooler 
months the cocoon stage is considerably extended. Segmenta- 
tion is visible in the egg some hours before it hatches. The 
larva works itself out of the thin shell, which then forms a sort 
of adhesive bed for it on the roach’s coxa. It is large-headed 
and its undulating mid gut shows a sort of orange color from 
