824 FIFTH KEPORT OF THE ENTOMOLOGICAL COMMISSION. 



The eyes are moderately finely granulated and completely divided. 

 The head is large, exserted, and in the S is deeply concave. The pro- 

 thorax is broader than long, and strongly asperate in front in the 9 , less 

 in the S . The tibiae are dilated, finely serrate on the outer edge, rounded 

 at tip, and very feebly mucronate at the inner angle ; the tarsi have the 

 joints 1-3 rather stout, nearly equal in length; fourth very small, fifth 

 slender, as long as the second and third united, with simple divergent 

 claws. The hairs are not serrate or verticillate, as in Pityopthorus, but 

 slender and smooth. 

 The four species in our fauna are easily recognized : 



Elytra with well defined striae of punctures, interspaces nearly smooth 2. 



Elytra with ill-defined distant rows of punctures, interspaces equally strongly punc- 

 tured, pubescence erect, abundant 4, politus 



Prothorax finely and sparsely punctured at the sides towards the base 1, retusus 



Prothorax finely but less sparsely punctured at the sides towards the base. 2, bivittatus. 



Prothorax scabrous and granulate behind the middle 3, acairicollia. 



X. bivittatus Mannh., Bull. Mosc. 1858, 236 ; Apate biv., Kirby, Faun-Bor. Am. iv, 

 192, PI. 8, Fig. 5 ; Boairichus cavi/rons Mannh., Bull. Mosc. 1843, 297 ( <? ) ; ibid, 

 1852, 359 ; Xylolerm cav., Mannh., ibid, 1852, 385. 



Maine, Canada, Alaska, Vancouver's Island ; length 3-3.3™". 12-13 

 inch. Varies greatly in color. Usually the front part of the prothorax, 

 the suture and the margin of the elytra are black ; sometimes only a 

 short, pale stripe is seen on each elytron. (Identified by Dr. Horn.) 



Mr. Schwarz remarks that Eichhoff cites this species as a synonym of 

 the European X. lineatus Oliv., and adds "I think he is right. His X, 

 vittiger described from California, is undoubtedly only a color variety 

 of the same species." (Ent. Amer., ii, p. 41.) 



2. The spiny spruce bark-boker. 



Xyleborua ccelatus Zimmerman. 



Order Coleoptera ; family Scolytid^. 



(Larva, Plate xxiv; figs. 2, 2b ; pupa, 3, 3a.) 



As theforegoing species has smoothed unarmed elytra, we have named 

 it the "unarmed spruce bark-borer," while the present species, which is 

 also destructive to spruce, though abundant in pine trees (p. 175), being 

 gouge-shaped at the end of the body with two prominent teeth on side 

 we would name ••' the spiny spruce bark-borer." Its habits and mines 

 are apparently like those of the foregoing species, but the mines are 

 a little larger, as is the beetle itself. We noticed the beetles in great 

 numbers with several pupas under the bark of the spruce at Brunswick, 

 August 22, and under another tree, observed August 27, there were 

 many pupse, and numerous pale beetles which had only recently cast off 

 their pupal skins. There were all stages between very pale beetles and 

 the dark, black-brown fully mature beetles 5 some with a short, broad 

 dark stripe on each wing-cover ; this might be thought at first sight a 



