PARASITIC ON SPIDERS. 235 
quitted the spider, which was found dead and much 
shrunk at the bottom of the phial, and attaching 
itself to the extremity of the cork with which the 
phial was stopped, it began to spin its envelope. 
On the 31st it had completed its cocoon, which was 
composed of pale yellowish-white silk of a compact 
texture, and measured one third of an inch in length 
and one tenth in diameter; it was of an oblong 
quadrilateral figure, tapermg’ to its extremities, one 
of which was more pointed than the other, and 
was connected with the cork by numerous fine silken 
lines. The perfect insect came out of the cocoon, at 
the larger end, on the 27th of June, and proved to be 
a female. 
The length of this insect from the anterior part of 
the head to the extremity of the abdomen, not in- 
cluding the ovipositor, was one fourth of an inch; 
the breadth from tip to tip of the anterior wings, 
when expanded, $4. The antennz were filiform, and 
had each twenty-four joints. The maxillary palpi 
had five joints, and the labial palpi four. The tibiz 
were terminated by two spurs on the underside. 
The tarsi had five joints, of which the penultimate 
was the shortest, and the claw-joint was provided 
with two curved claws and a pulvillus. The head, 
antennz, and several parts of the trunk were of a 
brownish-black colour, with the exception of the 
organs of manducation, which had a brown hue. 
An oblong, soot-coloured spot occurred near the ex- 
