12 
top of the tree, and excavates three or four long longitudinal galleries 
from a single entrance and broad central chamber (PI. II). The cen- 
tral chambers and galleries are usually grooved in the surface of the 
wood, but can be readily distinguished from those made by the Oregon 
Tomicus. It is a common and widely distributed species over the 
greater part of the pine-producing areas of the United States from 
the Atlantic coast to and including the Rocky Mountain region.* It 
attacks all of the Eastern and Southern pines, and doubtless several 
of the Western pines in addition to the rock pine, in which it was 
found in large numbers 
inthe Black Hills region. 
The wood -engraving 
Tomicus (Tomicus cala- 
tus Eichh.).—This is a 
much smaller and more 
slender bark beetle than 
the two preceding spe- 
cies. Individuals vary 
in length from 2.6 mm. 
to 3.2 mm., and in color 
from dark red to dull 
black. This is also a 
common, widely distrib- 
: uted, and variable spe- 
cies. It extends from 
\ the Atlantic to the Pa- 
cific, and infests all of 
the Eastern and South- 
ern pines and spruces. A 
variety (var. scopulorum 
n. var.) was found in the 
rock pine of the Black 
Fic. 4.—Work of the Oregon Tomicus. Primary galleries en- Hills, and has been col- 
graved in surface of wood. Central chamber extending into lected by the writer from 
wood. Reduced about one-half (original). £ 
a number of other spe- 
cies of Western pines. It attacks and breeds in the inner bark on the 
roots, trunks, and branches of weakened and dying standing trees of 
all ages and sizes, from the very young to the oldest and largest. It 
also breeds in immense numbers in the stumps, logs, and tops of 
recently felled trees. 
The dark-red turpentine beetle (Dendroctonus valens Lec.)—This is the 
largest of the known North American bark beetles. The adults vary 
in length from 6mm. to9.5mm._ It attacks the bark on the base of liv- 
“The Western form seems to be sufficiently different in some minor characters to 
warrant this distinction in variety name—occidentalis. 
