532 



FAMILY SCOLYTIDAE 



entered the tree by the same hole (see tig. 341, f, d (p) ). After the preparation 

 of this chamber, it is probable that fertilization takes place and the 6 beetle 

 then leaves the tree to die. When attacking small branches the $ now bores 

 a tunnel vertically down into the sapwood, either at the centre or in a corner 

 of the pairing-chamber (fig. c, d (/)), until it reaches the pith of the branch; 

 she then mines out a gallery (fig. c, d (c)) running in the longitudinal axis of 

 the branch, and at right angles to her former direction, about half an 

 inch in length on either side of the vertical bore. The eggs, I think, are 

 probably laid in this tunnel, and the larvae perhaps mine up and down 

 both ways, but this latter has to be corroborated by further observations. 

 In one or two instances it was noticed that the ends of the gallery in the 

 pith were blocked up with plugs of what appeared to be chewed-up pith, 

 in which the eggs may have been laid. When the female is disturbed in the 

 pairing-chamber, in which she apparently lives for some time after egg-laying, 

 she at once retires down into the gallery in the pith by the vertical boring (/). 

 In the case of larger branches only the hole at one side of the pairing- 

 chamber and the egg-galleries, which are usually curved and branching, 

 deeply groove the sapwood (see fig. f(). Indentations at irregular intervals 

 are cut in the sides of the egg-gallery, in which the eggs are laid. The 

 larvae feed almost entirely in the bast in which the larval galleries are bored. 

 Fig. or shows a portion of a branch badly attacked by this pest in which the 

 galleries are so interlaced as to render it difficult to decipher them. This is 

 the usual appearance of old attacks in the forest. 



As this Cryphalus lives at a somewhat low elevation in hot valleys (the 

 altitudes at which it was found were between 2,500 and 3,000 ft.), it is 

 probable that the June beetles observed egg-laying were laying the eggs of 

 the second generation of the year. Just a month later, however, in the first 

 week in Jul}/, the beetles were observed again egg-laying, this time all the 

 pairing-galleries and many of the mother egg-galleries having been already 

 prepared. No S beetles were found at this period. This means that either 

 the June-July generation is run through in all its stages in a month, or (what 

 is perhaps more probable) that there are several generations of these insects 

 in the year and that the different life-cycles overlap. 



From some branches taken down to Dehra (elevation 2,000 ft.) I l)red 

 out beetles in the middle and third week of September, and others about the 

 end of the first week of October. 



This is a more dangerous pest than its smaller companion Cryphalus, 

 since its galleries and boring operations are on a more 



Damage Committed ^^^^^^^-^^^ g^ale. Saplmgs and branches of older trees 

 in the Forest. r r> 11 



heavily attacked by the beetle lose their needles, which 



first turn yellow and then drop off. An examination will show circular 



entrance-holes large in comparison with the minute ones of the smaller 



Cryphalus, and these will be seen to be equally as numerous on the outer 



surfaces of the thicker bark as in the interstices between the flakes. The 



