1899-1900.] Dr E. S. MacDougall on Scolytus multistriatus. 359 
The Biology and Forest Importance of Scolytus ( Eccopto - 
gaster) multistriatus (Marsh). By R. Stewart MacDougall, 
M.A., D.Sc. Communicated by Professor Cossar Ewart. 
(Read June 4, 1900.) 
The Scolytidse is a family of small roundish tetramerous 
beetles characterised by the fact that the female beetle enters 
bodily the tree or plant for her egg-laying, the eggs being 
generally laid in little notches cut out in the sides of the mother 
gallery. With some species, however, the eggs are laid all 
together in a hunch. The grubs are whitish, wrinkled and 
legless, and have brown scaly heads. The close resemblance 
to each other of the grubs of the various species renders the 
determination of the species from larval characters extremely 
difficult, if not impossible, hut the figures or patterns presented 
by the mother gallery and the larval galleries in relation to it 
are in general so highly characteristic, that with these and the 
name of the host plant one can generally determine the species. 
The family Scolytidse numbers in it some of the very worst 
insect enemies of our woods and felled trees. Some do harm 
as imago by gnawing the roots of conifers ; some, both as imago 
and grub, attack the hast of grown conifers; others, again, like 
Hylesinus jpinijperda — that scourge of our pine-woods — do harm 
as newly-issued imagines by tunnelling into the young shoots, 
and later, both as imago and larva, boring their galleries in the 
cambial region, interfering with the conduction of sap, and 
weakening or killing the tree; while members of still another 
group bore into the wood and render it useless for technical 
purposes. 
Among the six species of Scolytus given by Fowler as British, 
we have enemies of the birch, oak, and elm. Two species attack 
elm, viz., Scolytus destructor , Oliv. ( Geoffroyi , Goetze), the larger 
elm bark beetle, and Scolytus multistriatus, the smaller elm 
bark beetle. 
