52 TRANSACTIONS OF ROYAL SCOTTISH ARBORICULTURAL SOCIETY. 
VI. Megastigmus spermotrophus, Wachtl, as an Enemy of 
Douglas Fir (Pseudotsuga Douglasii), with two Plates. 
By R. Stewart MacDovuca.i, M.A., D.Sc., F.R.S.E., 
Hon. Consulting Entomologist to the Society. 
In the month of May 1905 I received a number of seeds of 
the Douglas fir that had been sent by Mr John Crozier, Forester, 
Durris, Aberdeenshire. Accompanying the seeds were some 
insects that had issued from them. The insects, on examina- 
tion, proved to be Jegastigmus spermotrophus. From these seeds 
and from others I bred out a number of males and females of 
this species. The infested seed had been rendered useless by 
the destructive work of the JZegastigmus larve. In the letter 
containing the request for determination of the insect and how 
to combat its ravages, Mr Crozier wrote: ‘The insect has, for 
some years back, been causing a serious loss to our stock of 
Douglas fir seed. I noticed its presence on coming here nine 
years ago, but it had no doubt been in the estate before that 
time. Seed was plentiful, however, and as the damage was 
comparatively trifling, I did not pay much attention to the fact. 
Now, however, it has assumed a more serious aspect, as the 
seed on many of the older trees from which I formerly collected 
my supply, in good years amounting to over 300 bushels, is 
not worth the trouble of gathering. I have raised some millions 
of plants on this estate, but unless this pest can be kept in check, 
it will be impossible to keep up the stock from home-grown 
supplies.” 
A number of points render this communication of Mr Crozier’s 
interesting. 
In the first place, this is the first record of the insect in our 
country. Mr W. F. Kirby very kindly wrote me to say that 
while two other species, Megastigmus collaris, and the large 
Californian species, MJegastigmus pinus, were in the Collection 
at the Natural History Museum, the present species, JZ. 
spermotrophus, was not represented. 
The insect occurs, too, as an enemy on a tree of great value, 
both for ornament and for timber, and justly regarded as one 
of the most important trees introduced in the last century. 
Although introduced into Britain only seventy-eight years ago, 
there is a specimen in our country 130 feet in height, and thick 
