329 
1915-16.] Structure and Life-History of Bracon sp. 
The Bracon cocoons may be mistaken for pieces of fungus mycelium, 
but a little practice soon enables one to recognise them. 
The pine stump, as is well known, affords a breeding-place for many 
other insects than this Bracon and Hylobius abietis. Of these the bark 
beetles are of most interest. They comprise three species — Myelophilus 
piniperda, Hylastes ater, and Hylastes palliatus. Another pine weevil, 
Pissodes pini, also inhabits the Scots pine stump. Its larvrn resembles 
a half- grown Hylobius grub, but it lacks the furrows on the epicranium 
(Plate II, figs. 9 and 10). A further distinction is afforded by the spiracles : 
in Pissodes these are circular, in Hylobius elliptical. Two longicorn 
beetles and their larvae are occasionally found — Rhagium bifasciatum 
and R. indagator. 
I have obtained only one other insect enemy of Hylobius, viz. the 
Ichneumon Ephialtes tuberculatus. At Kingswells, Aberdeenshire, I 
found two large brown cocoons, to each of which was attached the head 
of a Hylobius larvae. These proved to be the cocoons of Ephialtes 
tuberculatus. From one of them a female emerged ; the other con- 
tained a dried male pupa. I have identified the species from Morley’s 
description of it. E. tuberculatus has not hitherto been recorded as 
parasitic on Hylobius in this country. Ratzeburg records it on Hylobius 
in Germany. 
Field Observations. 
Date. 
County and 
Locality. 
Date of 
Felling. 
1914. 
Sept. 
Woodlands, 
Banchory 
Devenick 
estate, Kin- 
cardineshire 
1911 
55 
Woodlands, E., 
adjoining 
the above 
1912 
55 
Woodlands, E., 
near the above 
1914 
55 
Hazelhead 
estate, Aber- 
deenshire 
1913-14 
Bracon. 
Old cocoons 
plentiful 
Two batches 
of cocoons 
One batch 
of cocoons 
Three batches 
of fresh 
cocoons 
Other Insects. 
Old galleries of 
M. piniperda 
Old galleries of 
M. piniperda 
Adults and lar- 
vae of H. ater 
and H. palliatus 
Adults and lar- 
vae of H. ater 
and M. pini- 
perda 
Remarks. 
Area examined in 
1913, only a few 
stumps being left. 
The area consis of 
pure Scots pine. 
Only four stumps in 
this area yielded 
weevil grubs, the 
remaining stumps 
being attacked by 
fungus. 
0 nly one stump yield ed 
Hylobius larvae, the 
area being freshly 
felled. 
The area consists of a 
mixed wood, chiefly 
beech and Scots pine, 
in which occasional 
trees have been cut. 
The stumps are 
widely scattered. 
