230 INSECTS INJURIOUS TO FOREST AND SHADE TREES. 
beetle, that we feel justified in supposing that it must have been feeding 
on them. 
In the genus Xyloterus, according to Leconte (Rhyncophora, p. 357), 
the club of the antenn is oval, compressed, and solid, without articu- 
lations; the shining corneous part extends forwards in a narrow band as 
far as the middle, except in X. politus, where it is entirely basal, and 
the club is indistinctly divided by one round suture; the rest of the sur- 
face is opaque, finely pubescent, and sensitive. The funicle is composed 
of two parts, as in the two preceding genera; the first joint is large, and 
stout as usual, the remaining part is about equal in length, forming a 
pedicel to the club, and is divided by two not well marked transverse 
sutures, thus causing the funicle to be 4-jointed. The eyes are moder- 
ately finely granulated and completely divided. The head is large, ex- 
serted, and in the #7 is deeply concave. The prothorax is broader than 
long, and strongly asperate in front in the 2, lessin the é. The tibize 
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 yerticillate, as in Pityopthorus, but slender and 
smooth. 
The four species in our fauna are easily recognized : 
Elytra with well defined striz of punctures, interspaces nearly smooth.-...:....-- 2 
Elytra with ill-defined distant rows of punctures, interspaces equally strongly punc- 
TURed spubescence erect, abundante.- 42 sceeete sss ee oe ee eee 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, scabricollis. 
X. bivittatus Manuh., Bull. Mose. 1858, 236; Apate biv., Kirby, Faun-Bor. Am. IV, 192, pl. 
8, fig.5; Bostrichus cavifrons Mannh., Bull. Mose. 1843, 297 (¢); ibid, 1852, 359; 
Xyloterus cav., Manuh., ibid, 1852, 385. 
Maine, Canada, Alaska, Vancouver’s Island; length 3-3.3"™; .12-13 
inch. Varies greatlyin 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.) 
7. THE SPINED SPRUCE BARK-BORER. 
Xyleborus celatus Zimmerman. 
Order COLEOPTERA; family SCOLYTID2. 
As the foregoing species has smoothed unarmed elytra, we have named 
it the “unarmed spruce bark-vorer,” 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 each side 
attheend, we would name “the spined spruce bark-borer.” Its habitsand 
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 
