286 FAMILY CERAMHYCIDAE 



Tetropium sp. 



Referenxe.— Mr. Gahan identifies this as a species of Tetyopium near to the European /ksckw, Fabr., but 

 requires further specimens to make certain of the identification. 



Habitat. —Deota, Tehri Garhwal, and Simla, North-West Himalaya. 

 Tree Attacked. — Spruce {Picea morinda). Deota, 

 Simla. 



Beetle. — ^ A stoutish beetle. Head and prothorax black, 

 covered with a vellow pubescence when living ; head and thorax 

 punctate. Antennae about same length as 

 Description. insect, brown in colour, basal joint large. 



Legs long, dark brown, with broadly ovate 

 flat fetnora. Elytra brown with a purplish tinge, and a yellowish 

 pubescence on basal portions ; each with two well-marked raised 

 lines running down it. Under-surface black, the abdominal seg- 

 ments thickly set, especially laterally, with short yellow pubescence. piQ_ jgg^ 



Length, i6 mm. Tetropium sp. 



$ Slightly longer and narrower than $. Thorax narrower and North-West Himalaya, 

 shorter, head smaller ; elytra narrower across base and leave the 



pygidium exposed. Antennae shorter than body, about half length, the basal joints less 

 swollen than in (J. Femora of posterior legs not so enlarged and flattened. Under- 

 surface black, more or less shining on head and thorax ; abdominal segments shining, 

 with only a slight pubescence laterally. Length, 19 mm. 



The beetle appears on the wing about the middle of June, pairs, and 

 lays eggs in spruce-trees. From the appearance of the 

 Life History. trees in which beetles and grubs have been taken it 



would seem probable that this beetle will lay in trees 

 almost if not (juite dead, and that the grubs can feed upon bast which has lost 

 the greater amount of its sap. In this respect this insect would appear to 

 differ in its habits from the deodar Tetvopium, whose larvae require perfectly 

 fresh bast to feed upon. The larvae feed in the bast and sapwood, eating out 

 long winding galleries five to seven inches in length, which have a general 

 direction parallel to the long axis of the tree. These galleries are packed 

 with wood-dust and excreta. When full-fed the grubs tunnel down into 

 the sapwood and eat out a small elongate chamber parallel to the long axis 

 of the tree and pupate in this. In the cases where the tree infested is an old 

 one with a thick bark on the lower parts of its trunk the larvae eat out their 

 pupating-chambers in the thick bark instead of going down into the sap- 

 wood. The larvae spend from about the end of June to February or the 

 first part of March in this stage, and then pupate, about five or six weeks being 

 spent as a pupa, and the balance in the resting stage as a beetle. I cut 

 out a beetle in this resting stage from its pupal chamber in a large standing 

 dead spruce-tree in the Simla Catchment Area on 11 April igo8. The pupal 

 chamber is from half an inch to one inch down in the sapwood. The en- 

 trance to it is blocked up with wood fibres. The beetle bores straight through 

 the bark to escape from the tree when mature, and I have noticed that the 

 escape holes are generally situated in a crevice, so that on issuing the beetle is 

 sheltered from the gaze of birds, insect foes, etc., by theoverhanging bark flakes. 



