1927] 
Observations on Wood-boring Insects 
73 
OBSERVATIONS ON WOOD-BORING INSECTS, THEIR 
PARASITES AND OTHER ASSOCIATED 
INSECTS . 1 
By Charles T. Brues 
During the course of many years’ interest in the several 
groups of Parasitic Hymenoptera the writer has frequently been 
struck by the preponderance of primitive types* which prey 
upbn wood-boring insects. Not only this, but several of the 
most primitive families of phytophagous Hymenoptera develop 
mainly within the tissues of woody plants and an exceptionally 
large proportion of the leaf-feeding sawflies subsist upon the 
foliage of trees. These facts suggest that the early phylogenetic 
history of the Hymenoptera was in some way bound up in the 
deveopment of the woody flora and that this early association 
has persisted to the present time without sufficient change to 
destroy the earmarks of past history in the modern hymenop- 
terous fauna. 
The immediate occasion for the present discussion is a 
small, but quite varied collection of insects made during the 
past summer at my summer home in Petersham, Mass. Early 
in the season the attention of my wife was attracted by a con- 
siderable number of flying insects that had congregated upon 
the panes of a window in a room where the stove wood for the 
household is stored. This room contains an assortment of wood 
of various sizes and varieties, principally oak, chestnut, white 
pine, red maple and birch. The wood is cut in the nearby wood- 
lot one year, allowed to season and then sawed, split and stored 
away the next year. Before storage, it has therefore an oppor- 
tunity to be attacked by various wood boring insects and fungi 
together with the insects that are attracted to the latter. 
So many specimens appeared on the first day that collec- 
tions were made daily upon the window from early July to late 
September and by the end of the season we had amassed a con- 
siderable collection. After sorting and identification, the fol- 
1 Contribution from the Entomological Laboratory of the Bussey Insti- 
tution, Harvard University, No. 275.) 
