AMERICAN COLEOPTERA. 161 



this species are less dilated and less distinctly serrate than in those 

 above mentioned. 



14. X. plagiatus. — Less slender, ferruginous brown, shining, thinly clothed 

 with long erect hairs ; antennce and legs paler ; head convex, punctured, with a 

 triangular, opake, pubescent, frontal spot; prothorax scarcely longer than wide, 

 sides parallel behind, then semicircularly rounded with the apex; base very 

 distinctly rounded towards the sides, surface strongly roughened before the 

 middle, finely but deeply punctured behind, with a smooth oval space each 

 side just behind the middle; elytra strongly but not densely punctured, punc- 

 tures not arranged in rows ; posterior declivity strongly toothed ( 'J, ), or almost 

 unarmed ( 9 ) scarcely punctured, siiture elevated. Long. 2 mm. 



Male with the posterior declivity of the elytra deeply concave, with the 

 margin semicircularly elevated from near the tip to near the suture, armed at 

 its upper limit with a robust horn, slightly hooked at the tip, then with two or 

 three denticles, and ending below in a rather prominent tooth. 



Female with the posterior declivity somewhat retuse eacih side, and deeply 

 sulcate near the suture, with a very small denticle near the suture, and a larger 

 subacute tubercle near the tip. 



Maryland, Mr. H, Ulke. I infer that these two foi'uis are the sexes 

 of the same species, on account of the identity in sculpture of the 

 thorax, and because the sexes of the European Tomicus hidc.ns as figured 

 by Ratzeburg, differ in a somewhat similar manner. 



The smooth basal portion of the antennal club is smaller in this than 

 in the other species, and the sutures of the apical portion are less 

 curved, being, in fact, nearly straight ; in these respects it tends to- 

 ,wards one of the groups of Tomicus (^pmi, I'nferruptus, &c.), but dif- 

 fers by the elevated margin of the posterior declivity not extending 

 to the tip, and by the sparse confused puncturing of the elytra ; the 

 tibiae are less dilated than usual, and armed with a few not very pro- 

 minent teeth, very nearly as in the preceding species, to which it is 

 evidently allied. 



C. — Body moderately slender, cylindrical, tip of elytra obliquely 

 declivous, scarcely flattened, without tubercles; funiculus of antennae 

 5-jointed — Dryoc(etes Eichhoff. 



15. X. septentrioiiis.=jBosi!r»cAMS sept. Mannh. Bull. Mosc. 1843, 298; Bostri- 

 chus semicasianeus Mannh., ibid, 1852, 358. 



Alaska, Lake Superior, Hudson Bay Territory, Canada, New York. 



With a large series of specimens before me, and types of both of the 



descriptions of Mannerheim, I perceive no differences which permit 



them to be distinguished as species. The specimens of semicastaneus 



have no appearance of a smooth dorsal prothoraeic line; the single 



AXvisk-Anaseptentrionis has it feebly apparent; in other specimens from 



Lake Superior, New York and Virginia it is quite obvious. 



