820 FIFTH REPORT OF THE ENTOMOLOGICAL COMMISSION. 
regions that the borers were the cause of the disease. This man re- 
peatedly removed the bark, and, as he said, u found it full of little white 
worms." Be also assured ine that he found similar worms in living 
Bprooe trees, and that the result of their work was to girdle the tree. 
From conversations with different lumbermen it appears that a spruce 
tree a foot in diameter gets its growth in from forty to fifty years. The 
larger trees can be culled out of the same lumbering region every ten 
years. Lumbermen have the impression that a spruce tree grows rap- 
idly. This of course depends on the soil, position, and climate. We 
have found the past season that spruce saplings about 4 feet high get 
their growth in three years ; it is easy to ascertain this by the difference 
in the color and appearance of the bark. Whether the spruce grows more 
rapidly than hard-wood trees remains to be ascertained. Standing in a 
yard of a house in Maine, a sugar- maple, which had been a rapid grower, 
and which we know to be about forty-eight years old, measured, in 
September, 1884, 1 foot from the ground, 24§ inches in diameter. The 
Thorudike oak, on the campus of Bowdoin College, raised from an 
acorn planted on the first commencement day of the college, on the first 
Wednesday of September, 1806, now measures (1885), at 1 foot from the 
ground, 30 inches in diameter, having therefore attained its present 
dimensions in seventy-eight years. 
From Mattawanikeag we went to Moosehead Lake. Throughout the 
great range of forests to be seen from the lake at and south of Mount 
Kineo no dead spruces were to be observed ; though a single bud-worm 
(Tortrix fumiferana) was beaten from a young spruce July 6. Here, 
however, as everywhere else, dead spruces occasionally occurred whose 
bark was filled with Scolytid beetles. 
From E. S. Coe, esq., of Bangor, to whom we are indebted for infor- 
mation regarding the destruction of spruce timber in Maine, we learned 
that large tracts of spruce timber near Kennebago Lake, on the height 
of land between the Androscoggin and Forks of the Kennebec, had been 
destroyed. 
Mr. Coe also informed us that he learned from General Smith, of 
Xorridgewock, that the spruce growth about that town and Waterville 
early in this century had been diseased, and died very much as in the 
past few years. 
From various persons we learned that the evil is now abating, and 
without doubt if the tracts of dead spruce, at least those near settle- 
ments or villages, could be cut down and removed, leaving, however, 
the spruce undergrowth, a new growth of spruce would spring up, 
which in forty or fifty years could be profitably lumbered. 
The disease due to bark and timber beetles. — From the foregoing state- 
ments the reader will justly infer that the great destruction of spruce 
and forest trees throughout northern New England in 1879, and four or 
five years following, was due to the attacks of beetles, chiefly the small 
cylindrical bark-borers, belonging to the coleopterous family Scolytida 1 : 
