9 
Iife-history of Boreus hyemalis. 317 
sparsely lines the walls. This silk hning is, in my opinion, 
by no means always present, although being never very 
noticeable I may have overlooked it. The larva now rests 
motionless. The legs become considerably shorter, espe- 
cially the second and third pairs. The change to pupal 
state usually takes place in September, but last year | 
found pupae in mid-August. 
The pupa is far more active than the larva, wriggling 
up and down the tube rapidly on disturbance. All the 
characters of the adult are visible, but the rostrum, and 
ovipositor in the case of the female, are somewhat shorter 
than in the adult. The wings of the male lie at the sides 
‘of the thorax, the legs and antennae also at the sides 
but rather more ventrally. The colour is at first white, 
then yellow, and just before emergence greenish brown. 
The imago appears in November after a pupal period of 
four to eight weeks. 
On the 21st September of this year I took sixteen female 
pupae and one larva about to pupate. Three young 
larvae, however, were also found, the smallest being 2 mm. 
long and the largest 2-5 mm. All were still feeding. 
Judging by the time usually taken in growth these larvae 
were probably not more than a week or two old, and if 
such is the case they may be the result of a summer brood. 
It is quite possible that a few pupate in summer and emerge, 
while the great majority are single brooded. I know that 
this happens with many normally single-brooded Neuro- 
ptera. On the other hand, this phenomenon may be due 
in some way to the long dry summer. My captive larvae 
have shown no tendency to early pupation. It will be 
interesting to see whether the specimens in question will 
emerge this year. Those previously noticed as being full 
fed on the 19th December continued until the following 
autumn as larvae. 
From one larva, taken when nearly full fed from the 
Forest, a single larva of a parasitic Hymenopteron emerged 
on the 3lst March. After making its way partly to the 
surface of the moss it commenced to spin a pale yellow 
cocoon between the moss plants vertically. On a former 
occasion I had found two yellowish cocoons about } inch 
long spun vertically between the moss plants, which 
cocoons belonged undoubtedly to the same parasite. 
Unfortunately they were not kept. The larva in question 
did not complete its cocoon, and hardly had it pupated 
TRANS, ENT. SOC, LOND. 1921.—PARTS III, IV, (JAN.’22) Y¥ 
