2 Mr. J. Blackwall on a Species of Ichneumon 



In April 1838, I captured a young female Epeira antriada 

 with one of these parasites upon it, and placing it in a phial 

 of transparent glass, I supplied it with flies. Towards the 

 end of May, having gone through its final moult and increased 

 considerably in size, this larva became very restless, and on 

 the 29th 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 tapering 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 the female of a 

 small species of Ichneumon ; but whether it is known to en- 

 tomologists or not I have not yet been able to ascertain*. 



The length of this insect from the anterior part of the head 

 to the extremity of the abdomen, not including the ovipositor, 

 was one-fourth of an inch ; the breadth from tip to tip of the 

 anterior wings when expanded, ||ths. The antennae were 

 filiform and had each twenty-four joints. The maxillary palpi 

 had five joints, and the labial palpi four. The tibiae were ter- 

 minated by two spurs on the under side. The tarsi had five 

 joints, of which the penultimate was the shortest, and the 

 claw-joint was provided with two curved claws and a pul vil- 

 lus. The head, antennae, and several parts of the trunk were 

 brownish black, with the exception of the organs of mandu- 

 cation, which were brown. An oblong soot-coloured spot oc- 

 curred near the exterior margin of each anterior wing, a little 

 beyond the middle towards the extremity. The legs, and 

 the maxillary and labial palpi, were of a yellowish brown 

 colour, the tarsi and the extremities of the tibiae of the pos- 

 terior legs excepted, which were brown. The abdomen con- 

 sisted of eight segments : the first, which was the longest, 

 was rather narrow and of a brownish black colour; the others 

 were dark brown above, but the posterior margins of the se- 

 cond, third, fourth, and fifth were much the darkest. The 

 caudal or terminal segment was the shortest, and had a small 

 hairy process on each side, at the extremity. All the seg- 

 ments, except the first, were pale brown on the under side of 



* Mr. Stevens, to whom we referred the insect in question, kindly in- 

 forms us that it is the Polysphincta carbonaria of Gravenhorst. — Ed. 



