FAMILY CERAMBYCIDAE 



587 



I have not yet ascertained whether this beetle exists in the forests in 

 any serious numbers. 



I have found parasitized dead grubs of this insect in their tunnels or 

 pupating-chambers in the wood, but I have never taken a specimen of the 

 parasite, which is possibly an ichneumon fly. 



North Zhob. 



Criocephalus. 

 Criocephalus tibetanus ? Sharp. 



References.— Sharp, Trans. Ent. Soc. ; Stebbing and James, A further note on the Chilgoza 13ark-boring 

 Beetles of Zhob, Ind. For. Records, i, p. 251. 



Habitat.— North Zhob Chil^i^oza Forests. Gahan states that the type 

 is from Tibet. 



Tree Attacked.— Chilgoza {Piiins gcrardiaiia). 



Beetle.— Head and prothorax dull black. Elylia dark 



aeneous brown, slightly lighter apically, dull ; antennae 



black, apical joints brownish. Front 

 Description. of head with a transverse furrow 



above clypeus, rugose and set with 

 tine transverse striae on vertex. Prothorax widest medianly, 

 sides rounded, the disk with three rounded depressions, the 

 two largest placed on either side medianly, the third just 

 above base on median line ; the surface covered with tine 

 irregularly transverse striae. Elytra wider than thorax at 

 base, slightly broader at level of hind legs and thence con- 

 stricting to apex, latter truncate and slightly spined in outer 

 angle ; striate-punctate, the striae not prominent, strongest 

 in basal half ; the punctures irregularly scattered, strongest in 

 basal half. Under-surface black, moderately shining, covered 

 with a fine short yellow pubescence. Length, 24 mm. to 28 mm. 



Larva.— A small white corrugated but slightly tapering 

 grub about an inch to i| in. in length when full-grown. 



When investigating the chilgoza bark-beetle attacks in the North Zhob 

 forests in 1905 it was noted that many of the infested 



Life History. trees contained numerous longicorn larvae feeding 



in the bast layer and sapwood. The grubs eat out 

 elongate winding galleries which groove both bast and sapwood, the 

 eggs being evidently laid by the beetle on the thin outer bark of the tree. 

 When full-fed the grubs bore down into the heart-wood and eat out in 

 it an elongate pupating-chamber parallel to the long axis of the tree. The 

 grubs seem to become full-fed about the end of June or first weeks in July, 

 the beetle appearing on the wing during August and ovipositing. The life- 

 cycle takes a year from ep,g to beetle, the grubs hatching from the August 

 eggs hibernating as such in their tunnels in the tree. 



Not having taken the perfect insect during my visits in June and again 

 in November 1905, I made no allusion to this insect in my monograph 

 entitled Note on the Chilgoza Bark-boring Beetles of Zhob* In a letter received 



* Foj-est Bulletin., no. 3, 1905. 



P^lG. 197. 

 CrioccpJialiis tibetan us 

 North Zhob. 



Sharp. 



