FAMILY SCOLYTIDAE 



473 



HVLASTKS. 



Two species, whose life histories are partly known, infest Coniferae in 

 the Himalaya. 



Hylastes himalayensis, Stebbing. 



HkkkrknCKS.— Stebbing, IiuL For. Mem., /ool. Ser. vol. i, pt. ii, p. 14 (1909) I il^ii'- Depart. 



Notes (Hylastes sp.), i, 201. 



Habitat. — North-West Himalaya. 



Trees Attacked.— Spruce {Picea niorinda) ; Blue Pine {Pinus e.xcelsa). 

 Jaunsar, Kumiun, Chamba, Simla, 3,500 ft. to 8,000 ft. 



Beetle.— Elongate, sliining, dark red-brown to black, punctate. The third tarsal joint 

 wider than the preceding joints. Head smooth, shining, with scattered rather large punctures 

 on vertex ; a transverse median depression below vertex not reaching 

 Description. the sides ; rostrum somewhat constricted, widest at base, not carinate ; 



front roughly rugose-punctate, the punctures finer medianly and tlie 

 ruc^osities more prominent on the rostrum. Prothorax constricted at apex, 

 the sides angulate and sinuate ; punctate, the punctures of two kinds ; 

 largi squamulose and confluent on sides, finer and not confluent on disk 

 and anterior median portion. Elytra wider than thorax and twice as 

 long, widest at apex, sides very slightly rounded to basal fourth, and 

 thence slightly sinuate to base ; striate-punctate, the striae prominent and 

 punctured, the interstices rugose with short fins hairs. Under-surface 

 black, covered with scattered fine white hairs ; 

 middle coxae fairly wide apart. Legs dark reddish- 

 black. Antennae yellow, tibiae red-brown. Length, 

 3 mm. to 3.5 mm. 



The male beetle is of smaller size than the 

 female. 



The beetle appears on the win^^ 

 about the second 



Life History. \\eek in May at the 



higher altitudes at 

 which it lives, and is to be found in the 

 trees at various elevations up to the mid- 

 dle of June. Anothergeneration makes its 



appearance in September-October. The ^^ ,....,.... 



beetle, after tunnelling through the bark a, beetle : /', egg-galleries in a piece of blue- 

 of the tree, eats its way down into the pine v.ood. 

 heart-wood. The entrance-tunnel may 



go horizontally through the bark into the sapwood (in a standing tree), or 

 may be at an angle. In any event, on reaching the sapwood the angle is 

 altered, and the long egg-gallery taken at an angle to the entrance one. 

 Short offset galleries are eaten off on either side near the extremity, and 

 eggs laid in them. I have not yet taken the grubs of the insect, although 

 I have taken the beetle in considerable numbers during several years. 



The male and female pair in the tunnel inside the tree, and the male 

 appears to help the female in boring a portion at least of the long gallery 



Eu;. 31 I. — Hylastes himalayensis., Steb. 



