BARK BEETLES OF THE GENUS HYLASTES 11 
Proc. 17: 469; Hubbard and Schwarz, 1878, Amer. Phil. Soc. Proc. 17: 643; 
Schwarz, 1888, Ent. Soc. Wash. Proc. 1: 80; Packard, 1890, U. S. Ent. Comn. 
Rpt. 5, p. 724; Hichhoff and Schwarz, 1896, U. S. Natl. Mus. Proc. 18: 606 ; 
Hopkins, 1899, W. Va. Agr. Expt. Sta. Bul. 56: 448; Smith, 1900, Insects of 
New Jersey, p. 365; Skinner, 1905, Ent. News 16: 248; Felt, 1906, N. Y. 
State Mus. Mem. 8, v. 2, p. 752; Swaine, 1918, Canada Dept. Agr. Ent. Branch 
Bul. 14 (2): 78, 79; Leonard et al., 1928, N. Y. (Cornell) Agr. Expt. Sta. 
Mem. 101:517; Eggers, 1934, Ent. Nachrichtenbl. 8: 25-26. 
Tomicus porculus Erichson, Swaine, 1909, N. Y. State Mus. Bul. 134: 145. 
Hylastes carbonarius Fitch, 1857, Noxious Insects of New York, 4th Rpt., p. 44; 
Leconte, 1876, Amer. Phil. Soe. Proc. 15: 889 (as synonym of porculus Er.) ; 
Hichhoff and Schwarz, 1896, U. S. Natl. Mus. Proc. 18: 607 (as synonym of 
porculus Er.). 
Hylastes granosus Chapuis, 1869, Synop. Scolyt., p. 17 (extract from Soc. Roy. 
des Sci. de Liége Mém. (2) 3: 225, 1873); Leconte, 1876, Amer. Phil. Soe. 
Proce. 15: 389 (as synonym of porculus Hr.) ; Hichhoff and Schwarz, 1896, 
U. S. Natl. Mus. Proc. 18 : 606, 607 (as synonym of porculus Er.). 
Hylurgus cavernosus Zimmermann, 1868, Amer. Ent. Soc. Trans. 2: 149; Hichhoff 
and Schwarz, 1896, U. S. Nati. Mus. Proe. 18: 606, 607 (as synonym of 
Hylastes porculus Hr.). 
Hylastes cavernosus Zimmermann, Leconte, 1868, Amer. Ent. Soc. Trans. 2: 174; 
Hubbard and Schwarz, 1878, Amer. Phil. Soe. Proc. 17: 6483. 
Hylastes scaber Swaine, 1917-18, Canada Dept. Agr. Ent. Branch Bul. 14 (1) : 18; 
(2) : 77; Eggers, 1934, Ent. Nachrichtenbl. 8: 25. ; 
Hylastes swainei Eggers, 1934, Ent. Nachrichtenbl. 8: 25-26. 
Female.—Very dark reddish brown to black, 3.9 to 5.8 mm. long, about 2.85 
to 2.9 times as long as wide. 
Frons rather broad between eyes, frontal rectangle about 1.04 times as long 
as wide, nearly black throughout; epistoma deeply and broadly impressed at 
each side, epistomal margin concolorous, liplike as usual, with median epistomal 
lobe moderately broad and very short; median carina distinctly elevated, 
broader below, sharper above, ending in the arcuate transverse impression, 
which is moderately deep and wide across the middle, less so at sides; surface 
moderately shining, finely, densely, rather roughly punctured, granulate in 
part; hairs short and fine, longer and coarser and directed orad on epistoma. 
Hye finely granulate, about 2.1 times as long as wide, distinctly wider above; 
inner line entire. Antenna with first joint of club as long as others combined. 
Pronotum slightly narrower than elytra, about 1.17 times as long as wide, 
widest near middle (but somewhat variable), posterior outline weakly arcuate, 
posterior angles rounded, sides moderately, nearly evenly arcuate (often vari- 
able), feebly constricted just behind the rather broadly arcuate anterior mar- 
gin; surface feebly to moderately shining, moderately closely, coarsely, and 
deeply, but somewhat irregularly, punctured, much more finely and densely in 
front, asperate-punctate at sides; median line on posterior two-thirds feebly 
elevated, impunctate; disk glabrous, with short, very inconspicuous hairs at 
sides and behind. 
Elytra wider than pronotum, nearly twice (1.8 to 1.9) as long as wide; 
widest near base, with sides subparallel for two-thirds of their length, then 
arcuately converging and moderately narrowly rounded behind; striae moder- 
ately impressed, wide, with first one often wider and more deeply impressed 
than others, causing disk to appear slightly flattened; punctures deep, very 
coarse, often subquadrate, smaller anteriorly and on the sides, separated by 
less than own diameters; interspaces narrower than striae, second one wider 
than others, varying from weakly punctured and scarcely rugose to granulate 
punctate on disk, narrower, more convex, and more distinctly asperate or 
granulate behind on disk and especially on declivity; disk subglabrous, sides 
and especially declivity with rather numerous short hairs, none of them flat- 
tened or scalelike. First and fifth abdominal sternites each nearly as long as 
other three combined; last sternite slightly ascending posteriorly, narrowly 
rounded behind, moderately coarsely punctured, with hairs short, fine, and 
inconspicuous. 
Male.—Often shorter and slightly stouter, with strial punctures somewhat 
coarser and interspaces narrower; elytra narrowed on posterior third as in 
female but with caudal end more broadly rounded or even subtruneate; last 
abdominal sternite more broadly rounded behind, with a wide, shallow groove 
bearing longer, yellowish hairs in median line on posterior half. 
