BARK BEETLES OF THE GENUS HYLASTES Asia 
HYLASTES LONGICOLLIS Swaine 
Hylastes longicollis Swaine, 1918, Canada Dept. Agr. Ent. Branch Bul. 14 (2): 
78, 79-80. 
Female.—Dark reddish brown, 3.9 mm. long, about 3.1 times as long as wide; 
allied to gracilis but readily distinguished by the much narrower pronotum 
and the very coarse punctures on both the pronotum and the elytral striae. 
Frons rather narrow between the eyes, frontal rectangle about 1.2 times as 
long as wide, piceous, slightiy lighter below middle; epistoma depressed, weakly 
impressed at each side; epistomal margin somewhat thickened, piceous, its 
median lobe broad and very short, with the free end shallowly emarginate and 
anterior face broadly impressed on middle half; transverse frontal impression 
only slightly arcuate, moderately, rather indefinitely impressed; median carina 
nearly lacking on epistoma, finely and sharply elevated, ending in transverse 
impression; surface opaque to subopaque, densely, moderately finely granulate- 
punctate (not so finely as in gracilis), with rather abundant, stout, clavate 
hairs, little longer on epistoma. Eye finely granulate, more than twice as long 
as wide (narrower than in gracilis), slightly wider above; inner margin entire. 
Antenna with first segment of club distinctly longer than others combined. 
Pronotum about 1.28 times as long as wide, much narrower than elytra, 
slightly widest just in front of middle; posterior outline weakly arcuate; 
posterior angles rounded; sides behind diverging slightly to widest point, then 
convergently arcuate to the broadly rounded front margin; disk with the narrow 
interstices brightly shining between the coarse, dense, rather deep punctures 
on disk; punctures denser and rougher at sides and much smaller and denser 
in front; median line distinctly elevated, shining, moderately wide; vestiture 
moderately fine on disk, but distinctly visible and better developed than in 
gracilis, much coarser at sides and behind. 
Elytra much wider than pronotum (44:35), about 2.09 times as long as wide; 
sides straight and subparailel for nearly three-fourths of their length, then 
strongly narrowed with the extreme tip moderately rounded; striae moderately 
impressed, first more strongly so; punctures coarse, deep, very close, quadrate, 
smaller at sides; interspaces on disk narrower than striae, nearly flat, finely 
punctate, and confusedly granulate; vestiture very evident, consisting of rather 
fine hairs of moderate length on disk, coarser, stouter, and more numerous 
on declivity; ninth interspace moderately strongly convex behind. Last ab- 
dominal sternite moderately. convex, with dense, rather rough punctures of 
moderate size, moderately broadly rounded behind. 
Male-——Similar in general characters; with last sternite slightly shorter and 
somewhat more broadly rounded behind; surface slightly flattened behind, with 
no special development of haivs. 
Remarks.—Swaine’s type came from Atlanta, Idaho, without ree- 
ord as to host. The writer has studied specimens from Lake Tahoe, 
Placer, Summerdale, Sequoia National Park, Tulare County, and 
Ventura County, Calif.; Hood River, Oreg.; Columbia Falls, 
Mont.; and Black Hills, S. Dak. No definite host records are avail- 
able; one specimen was taken flying to felled ponderosa pine. 
HYLASTES EXILIS Chapuis 
Hylastes exilis Chapuis, 1869, Synop. Scolyt., p. 20 (extract from Soc. Roy. des Sci. 
de Liége Mém. (2) 3: 228, 1873) ; Leconte, 1876, Amer. Phil. Soc. Proce. 15: 388, 
389; Schwarz, 1878, Amer. Phil. Soc. Proc. 17: 469; Swaine, 1909, N. Y. 
State Mus. Bul. 184: 145; Swaine, 1918, Canada Dept. Agr. Ent. Branch Bul. 
14 (2): 79; Blackman, 1922, Miss. Agr. Expt. Sta. Tech. Bul. 11: 64. 
Female.—Dark reddish brown to piceous, 2.88 mm. long, about 2.97 times as. 
long as wide, with the frons longitudinally sulicate below and pronotum dis- 
tinctly granulate-punctate throughout. 
Frons very wide between eyes, frontal rectangle 0.93 as long as wide, piceous, 
with epistoma slightly reddish and epistomal margin piceous; epistoma broadly, 
not deeply, impressed at each side, elevated but not carinate in middle fourth; 
epistomal margin somewhat thickened and liplike, its median lobe rather broad, 
very short, broadly, shallowly emarginate at free end, impressed in middle 
