THE GENUS PISSODES AND ITS IMPORTANCE IN FORESTRY. oo 
when these should be proceeded with, is practically a very 
important one, I purpose to deal with it here in detail. 
The information we possess as to the generation of P. notatus 
we owe to Continental observers, and in the records which I will 
give it must be held in mind that in our climate these may be 
subject to variations. I understand that Professor Somerville has 
been making a series of observations on the generation of P. notatus 
in Britain. It goes without saying that these will be thorough, 
and one looks forward with interest and pleasure to the publica- 
tion of the details. Personally, I am engaged in some breeding 
experiments with notatus. These will not be completed for some 
time, but I will just say here what, so far as I know, has not yet 
been suspected, that possibly some of the difficulties may find 
their solution on the same lines as in the case of Hylobius abietis, 
and that notatws may have to be added to the not very large list 
of insects which possess the power of recopulation and repeated 
egg-laying. 
The various statements as to the generation of the small brown 
weevil may be brought together thus :-— 
First, the generation is normally a double one—ze¢., there 
are two broods produced in the year. 
Second, the generation is an annual or single one—7.e., one 
brood in a year. 
Third, there are, or may be, three broods produced in a space 
of two years. 
First, the generation is a double one. Henschel champions 
this view, which needs for its fulfilment a very early appearance 
of the mature weevils in spring time, as early as March. From 
eggs laid then larvee would be hatched, and after pupation a 
brood of beetles would appear in midsummer. These, in turn, 
would copulate and lay eggs, the beetles appearing to complete 
the cycle the same autumn, The autumn-appearing beetles would 
hibernate as such, starting to breed in the next March. My 
comment on this is that, while not impossible, for example, in 
exceptionally favourable weather conditions, it is little likely to 
be the normal condition. At any rate, one desires a little more 
evidence. 
Second, the generation is single or annual. The great mass 
of evidence is in favour of this. There is some difference of 
opinion, however, as to the details, one set of authorities 
considering that the winter is passed in the imago stage, 
VOL, XV. PART I. c 
