352 



FAMILY CERAMBYCIDAE 



This Xylotrechus is the well-known coffee-borer of Southern India, and 

 white-borer of Ceylon. The insect practically exter- 

 minated the coffee industry in the sixties. The grubs 

 tunnel up the stem of the plant and are often in such 

 numbers that the weight of the crown causes the stem to break off short owing 

 to its inability to support it. An inspection will show that the stem is a mass 

 of tunnels entirely riddling it, most of the wood having been removed by 

 the grubs. The tunnels are not clearly visible on the surface of a newly 

 cut stem at first owing to the fact that they are entirely packed with the 

 wood-dust and excreta of the grubs. 



In a coffee plantation not far from the Nilgiris in South Kanara, which 

 I inspected with the owner in August 1902, we found some of the bushes 

 full of larvae, the grubs being in the main stems and thicker branches. 

 The presence of the grubs is easily discovered. My companion took hold 

 of a bush and swayed the whole thing backwards and forwards. If it was 

 badly infested by the borer it broke off short, the fracture occurring in the 

 main stem below the head. Bushes infested in this manner invariably died, 

 he informed me. Here in the middle of August the stems were full of 

 larvae, each tunnel having a squarish section. The eggs are apparently 

 laid on the bark by the beetle in autumn, and there may be two genera- 

 tions in the year. (See Dr. Bidie's report to the Madras Government, 1869.) 



Good cultivation and not too dense a shade are considered the best 

 preventives. The planters on the West Coast of Madras prune infected 

 bushes or clear out and burn acres of infested trees in a severe attack. 

 This is done in June and July. Some also scrape the trees with the back 

 of a knife in winter or early in the year, and those who do this appear to 

 suffer less from the borer. It is probable that in this process the eggs laid 

 on the bark are scraped off and thus killed. 



Xylotrechus gahani, Stebbing, sp. nov. 



Habitat. Charduar Rubber Plantation, Darrang, 

 Assam. 



Tree Attacked. Ficits elastica. Charduar. 



Beetle. Elongate, narrow, with a yellowish pubescence covering 

 most of head and thorax and arranged in bands on the elytra. Head 



and antennae black ; disk of prothorax 

 Description. reddish purple, sides black ; elytra black, 



with the following yellowish bands : (i) 



a basal X- sna P ed hand consisting of a semi-lunar band on each 

 elytron meeting on suture ; (2) a transverse band behind the middle, 

 gradually broadening towards the suture and not meeting lateral 

 margin ; (3) a narrow apical band. Pygidium black. Head finely 

 rugose on vertex, slightly channelled between the eyes ; front with 

 a sparse yellow pubescence, the median carinae on front converging 

 and meeting just above the clypeus. Prothorax very convex, narrow 



FIG. 239. 



in front, widest just above posterior angles, sides rounded, rather Xylotrechus gah 



f**"\'l-C 1 ^lir i-tr*r~m*-n+-A T7* l-.i. * J . 1 1 1-1.1 -11 . 



mm. 



coarsely asperate. Elytra widest at base, sides slightly rounded to sp. nov. Assam. 



