184 Annual Report for 1905 of the Zoologist. 
the possibility of its having been contracted from diseased 
spruces is definitely excluded. 
If any members of the Society meet with cases of larch bug 
attack where there are not, and have not recently been, any 
spruces in the neighbourhood, they would greatly aid by 
communicating the fact to their Zoologist. 
In the present state of our knowledge spruce-larch mixtures 
should certainly be avoided, and where larch bug appears 
attention should be given to the spruces in the neighbourhood, 
and if they are few and diseased, they should be cut down and 
the branches burnt. 
For the sake of those who are not familiar with spruce bug 
and larch bug disease, it may be well in conclusion to describe 
them briefly. On the spruce the minute bugs come out from 
their winter hiding places under the bark early in April, and 
attach themselves to the bases of the young leaves, and lay 
eggs, which hatch into “larvae,” and begin sucking close at 
hand. The irritation they cause sets up an abnormal growth, 
much resembling a small pine cone, in the chambers of which 
the insects live. This is the spruce gall or “ false cone,” and 
the disease is manifested by the presence of numerous galls on 
the tree. The appearance of larch bug disease is entirely 
different. There are no “ false cones,” but in young trees the 
first indication of attack is on the needles, which bend in a 
characteristic manner where the insect begins to suck. Soon 
a white woolly matter is exuded, and at a later stage the 
twigs become flecked with it. On old trees it often covers 
large areas on the trunk, and looks very much like the familiar 
woolly scale of the beech. 
Any galls which are noticed on seedling spruces should 
be removed and burnt, but on older trees this measure is, of 
course, impracticable. Diseased trees are, however, benefited 
by spraying with paraffin emulsions in April, when the wing- 
less females are spreading over the branches. Larches may 
be sprayed with advantage at any time, as the bugs are not 
hidden away in galls. 
The Subterranean Aphis {Siphonophora fodiens). 
A correspondent who had taken up a number of two-year- 
old black-currant plants for transplanting noticed some insects 
at the roots, and sent specimens for identification. They 
proved to be the underground aphis known as Siphonophora 
fodiens. The case was interesting, inasmuch as it was at the 
roots of black currants that this aphis was first observed by 
Mr. Buckton, who describes it in his monograph on British 
Aphides. Since that time I find no record of its occurrence on 
black-currant roots, though it has occasionally been found at 
