THE LARGH LARCH SAWFLY. 155 
105 were placed in the trees, and it was found that the birds had 
occupied 56 per cent. of them. In 1911, 347 boxes were in 
position, and 229 of them were tenanted, an increase of 66 per 
cent. The species which use them most freely are the Tits and 
Starlings. The boxes are put up in the hard-woods as well as in 
those of larch, and the former are used more than the latter, 
but as the woods are only a few moments’ flight apart there can 
be no doubt that the birds brought up in the hard-woods 
are beneficial to the larches near by. It is certain that the 
number of birds in the woods has greatly increased as a direct 
result of providing nesting-boxes for them. I have watched at 
close quarters the Great Tit and Chaffinch taking the larve of 
N. erichsoni. They work their way along a twig, and then, 
fluttering off, seize a caterpillar, immediately returning to a 
stouter portion of the branch in order to devour it (the larve are 
freyuently at a point of the twig which will not bear the weight 
of a bird). In an infested planting which I had under close 
observation in 1910 there were many Tits present so long as 
the sawfly larve were on the trees, but as soon as they had 
dropped from them to spin up, the Tits left the locality—a 
significant fact. 
On dissecting a number of birds from a larch plantation 
which had been attacked, I found that the Great Tit was the 
bird which had fed most freely on the caterpillar. According to 
my experience this is also the species which is most ready to 
avail itself of a nesting-box for breeding purposes. There can 
be no doubt that the smaller Tits also take the larve, and I have 
noted flocks of Rooks and Jackdaws devouring them. Starlings 
have been seen feeding on the larve at Thirlmere; as has been 
previously noted, this bird takes advantage of the nesting-boxes 
there. It is therefore certain that the erection of artificial 
nesting-sites for birds is of considerable value in checking the 
Large Larch Sawfly; this has evidently been realised, for in the 
present spring (1912) several private landowners are imitating 
the Manchester Corporation, and putting up nesting-boxes in 
their larch plantings. In the Wythop Woods, near Keswick, 
Jays were said to be of the greatest service in reducing the 
pest. 
Hewitt states that during the winter months, when the larve 
