366 SCOLYTID^]. 



[LeConte. 



The first and second sutures of the antennal club are broadly curved at the 

 middle, and bent forwards at the sides as in the preceding species, T. rectus. 

 Length 4 mm. ; .16 inch. 



Northern and Western part of Atlantic district, extending to Canada and 

 Hudson Bay Territory. Harris, who is good authority upon Say's species, 

 indicates this as the one described by that author. It is destructive to 

 Northern pine forests in the same manner, but, as far as observation yet 

 goes, to a less extent than T. cacographus is in the South. I have there- 

 fore felt warranted in rejecting Dr. Zimmeraiann's determination of Say's 

 species, and have applied a different name to the insect which has caused 

 so great destruction to the pine forests of the Southern States. 



8. T. hudsonicus, n. sp. 



Specimens of a larger size (5 mm. ; .19 in. ), from Hudson Bay Terri- 

 tory have the elytral striae composed of much larger punctures, than in 

 T. pini, and the tooth of the fifth interspace has a tendency to become 

 thicker and curved. I would be unwilling to designate it by a separate 

 name, were it not that the sutures of the antennal club are not bent forward 

 at the sides, but are nearly straight. 



9. T. interruptus Lee., Tr. Am. Ent. Soc. 1868, 164; Eichhoff, Berl. 

 Ent. Zeitschr. 1868, 274; Bostrichus int. Mann., Bull. Mosc. 1852, 357. 



Alaska and Hudson Bay Territory. The teeth of the margin of the de- 

 clivity are arranged as in T. pini, and hudsonicus; the stria are composed 

 of still larger punctures than in the latter, and the punctures of the inter- 

 spaces extend forward, almost to the base. 



10. T. tridens Lee., Tr. Am. Ent. Soc. 1868, 164; Eichhoff, Berl. Ent. 

 Zeitschr. 1868, 274; Bostrichus tr. Mann., Bull. Mosc. 1852, 357. 



The scutellum is described by Eichhoff as smooth, but in my specimens 

 it is as distinctly channeled as in the five specimens of T. interruptus; as in 

 fact it is in all the preceding species except T. calligraphus and marginatus; 

 this channel is less distinct in T. plastographus than in the others, but at 

 best, is an illusive character of but little worth. 



Alaska, one specimen. Very similar to T. interruptus, but the punctures 

 of the elytral striae are larger and more distant, and those of the interspaces 

 nearly as large, though less numerous. The head is more finely granulate, 

 strongly retuse in front, with a broad frontal groove. This character is prob- 

 ably sexual rather than specific. 



11. T. avulsus Eichhoff, Berl. Ent. Zeitschr. 1867, 402; Bostrichus av. 

 Zimm., Tr. Am. Ent. Soc. 1868, 147. 



Southern States. A much smaller species (2.5 mm.; .10 inch); the 

 elytral striae are composed of close-set quadrate punctures; the interspaces 

 are wide, and as far as the sixth have only a few punctures near the declivity ; 

 the latter is more abrupt than in the others, and nearly perpendicular, but 

 deeply concave, and coarsely punctured, as usual, with, the sutural stria 

 deeply impressed; the tooth at the end of the second interspace is small, but 

 well defined; that of the third is wanting; those of the fourth and fifth are 



