80 



regular; the punctures coarse, deep, quadrate, extremely close so that the 

 partitions are thin transverse ridges, somewhat smaller at the sides; the 

 interspaces narrower than the strise on the disc, wider on the sides, flattened 

 although somewhat elevated on the disc from the depth of the strise; finely, 

 densely granulate-punctate, more coarsely granulate on the declivity, and 

 evidently pubescent with short yellow hairs, longer on the declivity. 



The venter is coarsely, densely punctured; the last ventral slightly 

 convex, densely, coarsely, roughly punctured, rather narrowly rounded 

 behind, and pubescent towards the hind margin, probably impressed behind 

 in the male as in gracilis Lee; the prothorax below very coarsely, densely 

 and roughly but distinctly punctured. 



Host trees. — Unknown. Type locahty, Atlanta, Idaho. Type No. 102. 

 We have one doubtful record from southern British Columbia. 



An undescribed species of Hylastes occurs in Ahies nohilis in Oregon. 

 We have only one specimen. 



The Genus Hylurgops Leconte. 



Leconte, Am. Phil. Soc. Proc, 15: 389, 1876. 



Key to the Species. 



I Bases of the elytra only moderately arcuate and not serrate; the elytral 

 interspaces subequally sculptured. 

 B The pronotum as wide as the elytra, margined at the sides, from 

 acutely to subacutely, from the base nearly to the apex; densely 

 clothed with long erect hairs on the upper surface. N. Mexico. 



grandicoUis Sw. 



BB The pronotum narrower than the elytra and not acutely margined at 

 the sides; the long hairs sparse. 

 C Stout species; the elytra subinflated behind; the pronotum deeply 

 sinuate on the sides in front; the mesosternum strongly pro- 

 tuberant; the third tarsal segment strongly widened and deeply 

 bilobed; the pronotum rather strongly margined at the base. 



PLATE 18. 

 IPID BEETLES— All Much Enlarged. 



Fig. 1, Hylurgops pinifex Fitch*. 



Fig. 2, Hylurgops pinifex Fitch*. 



Fig. 3, Hylurgops rugipennis MannK*. 



Fig. 4, Hylurgops subcostulatus Mannh.* 



Fig. 5, Platypus wilsoni Sw., antenna**. 



Fig. 6, Trypodendron betuloe Sw.; male above, female below*. 



Fig. 7, Trypodendron retusus Lee; male above, female below.* 



Fig. 8, Ips calligraphus Germ*. 



Fig. 9, Ips calligraphus Germ.* 



Fig. 10, Dendroctonus; proventriculus, showing diagonal lines on the disc*. 



Fig. 11, Leperisinus californicus Sw**. 



Fig. 12, Leperisinus aculeatus Say, pair, starting a tminel*. 



Fig. 13, Anisandrus pyri Peck*. 



Fig. 14, Anisandrus minor Sw.* 



Fig. 15, Anisandrus populi Sw*. 



Fig. 16, Anisandrus obesus Lee*. 



Fig. 17, Gnathotrichus retusus Lee**. 



♦Original. Author's illustration. 



