FAMILY SCOLYTIDAE 



473 



HYLASTES. 



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

 the Himalaya. 



Hylastes himalayensis, Stt-l>lin<;. 



REFERENCES. Stebbing, Ind. F>>r. .Man., Zool. Ser. vol. i, pt. ii, p. 14 (1909) ; ibid. Depart. 



Notes (Hylastes sp.), i, 201. 



Habitat. North-West Himalaya. 



Trees Attacked. Spruce (Picca inorinda) ; Blue Pine (Finns exceha). 

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



Beetle,^ Elongate, shining, 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 the 

 rugosities more prominent on the rostrum. Prothorax constricted at apex, 

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

 larg 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 fine hairs. Uuder-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. 



1 



The beetle 



wing 



Life History. 



FlG. 3 i i. Hylustt"* 



Steb. 



, | H . et i e : fi, e-gallerics in a piece of bin,- 



appears on the 



about the second 



week in May at the 



higher altitudes at 



which it lives, and is to be found in the 

 t rees at various elevations up to the mid- 

 dle of June. Another generation makesits 

 appearance in September-October. The 

 beetle, after tunnelling through the bark 

 of the tree, eats its way down into the pine wood. 

 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 an^le is 

 altered, and the long e^g-gallc-ry taken at an an-le to the entrance one. 

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



. f 



e.ugs laid in them. I have not yet taken the ^rubs 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 lea^t of the long gallery 



