12 
majority of the cocoons examined the caterpillars were contracted, but 
had not pupated. In one case, however, one had transformed to pupa, 
and near its posterior end were found a number of recently deposited 
eggs of the Pimpla. 
Further observations upon oviposition were made on September 13. 
On one cocoon containing a recently spun -up larva two of the parasites 
were seen ovipositing at the same time. One of them, after running 
about for a few seconds, suddenly thrust its ovipositor into the body of 
the larva, which commenced to wriggle in pain, but the parasite was 
undisturbed and pushed its ovipositor in to its full extent, remaining 
motionless in this position for about five minutes, during which time 
the abdomen slightly moved in a peristaltic manner as if forcing the 
eggs out and down through the ovipositor. It then withdrew the ovi- 
positor, turned around, took a step or two, and gave the caterpillar 
three thrusts in quick succession. It then went a little farther and 
gave several more thrusts, and continued the same operation four times 
more, when it again thrust its ovipositor in as far as the body, remain- 
ing in this position again for several minutes. When the cocoon was 
examined, tour eggs were found loose inside the cocoon. Here again, 
however, nothing was reared. Another one was observed ovipositing 
in a recently spun-up larva. It was seen to thrust the ovipositor in 
three times, lasting one minute, one and one half minutes, and one-half 
minute. It was also noticed to thrust the ovipositor in at another place 
in the cocoon five or six times in quick succession, as if in search of the 
larva. When the cocoon was examined four eggs were found, all in a 
bunch between the first and second segments, and in an upright posi- 
tion, but so loosely attached that they became detached after the cocoon 
had been slightly handled. It seems as though the preliminary sting- 
ing of the caterpillar were done to quiet it so that the eggs when laid 
would not be detached by its struggles. A parasite placed in a tube 
with a larva which had been stung was later found to have deposited 
five eggs, which were adhering to the glass and not to the larva. 
An observation was made September II, which indicated that all of 
the larvae do not feed externally, since from a discolored caterpillar 
collected September I and placed in a tube a larva of this Pimpla 
issued on September 14, and spun a cocoon, the adult issuing Septem- 
ber L>0. 
It sometimes happens that a larva is stung when just on the point 
of transforming, and in such a case the transformation to pupa is occa- 
sionally accomplished. The recently formed pupa is also occasionally 
stung, as has just been shown. Contrary to the general rule holding 
when caterpillars are eaten out by the Pimpla larva*, they seem to feed 
within such pupa 1 , and eventually to spin their cocoons within the Orgyia 
pupa skin. Several times in December, 1896, apparently perfect female 
pupae of the Orgyia were found within their cocoons, with a closely 
applied layer of four or five Pimpla cocoons and a single break in the 
