574 ae Powell on the 
by the parasite. Dr. Chapman has found that ichneumoned 
larvae are sometimes stimulated into more rapid growth 
by the parasites, but there are also cases in which an 
opposite effect is produced, and this looks as though it 
might be one. 
Dr. Chapman very kindly handed the larva over to me. 
It had the dark dorsal line more distinct than in my 
5th stage specimen. There is a fairly distinct, whitish, 
double subdorsal line swelling out slightly on each segment 
and contracting towards the incisions. The ground colour 
is rather lighter than in my specimen. With the micro- 
scope I see that the double, white subdorsal line consists 
mainly of large, white, hair tubercles arranged in rather 
irregular line. The hairs seem a little darker than in the 
other larva. The lenticles are not numerous. There is 
one well outside the central dorsal line on the first sub- 
division of the abdominal segments and another on the 
lower edge of the white subdorsal line on the third sub- 
division. Thoracic plate (scutellum) black and shiny, more 
conspicuous than in the larger larva. Lateral area with a 
dull orange suffusion along the abdominal segments. This 
caterpillar made a small tent in the Potentilla leaves and 
shut it up pretty closely. 
Opening the tent on April 21, I found the larva dead. 
Its skin was inflated by the cylindrical cocoon with rounded 
ends, of anichneumon, ‘The cocoon had not broken through 
the larval skin, which was now dark grey, lighter on ventral 
surface, and with two suffused black dorsal blotches. 
From the dead larva a small ichneumon emerged on 
May 2, through a hole it made in the skin.* 
The full-grown larva which I had reared from the egg, 
settled itself for pupation about April 19. It had not then 
changed colour. 
On April 21 the whole dorsal and ventral area had 
become dull reddish, with the exception of a livid, whitish 
patch on the sides of the thoracic segments. This patch 
was sharply defined on its upper edge where it met the 
dull red colour of the dorsum. 
The plant had been exposed to the sun, and I feared 
that, in spite of its thick tent, the larva had been killed by 
overheating, for caterpillars that have been killed by 
* Mr. Claude Morley reports this specimen is a species of Lim- 
nerium, a male, and that its ‘pupa looks as though the Limnerium 
were hyperparasitic on Rhogas sp.” 
