294 FAMILY CERAMBYCIDAE 



prothorax is relatively not so wide as in larger males ; it is possible that 5. laticolle, Pasc., 

 founded upon a large male from Batichan Island, is only a form in which the prothorax 

 has reached its maximum of development." 



Larva. A whitish-yellow, thick-set, tuberculate grub, 

 with a dark brown head, black mandibles, light brown 

 shining prothorax broader than first abdominal segment ; 

 abdominal segments taper slightly posteriorly, all save the 

 last two, with an elliptical-shaped area of minute tubercles 

 on the dorsal surface. Length, 37 mm. 



FIG. 204. 

 There can, I think, be little doubt that this Larva of stromaiinm 



is the true Kulsi Borer of longicornc. 



Life History. teak, the insect of which 



Mr. A. G. Mien, I.F.S., studied the life history in 1877, 



and of which he wrote an account in the Indian Forester in 1879. Mr. Mien 

 found that larvae were present in infested stems throughout the year, and so 

 was of opinion that the insect passed through two generations in the year. 

 The grubs were first observed to be injuring the trees in 1873, but the mature 

 insect was not discovered until 1877. At the end of March in that year 

 Mr. Mien collected some sections of stems containing larvae .and kept them 

 under observation, obtaining beetles from them on 21 June. The pupating 

 and resting stage is thus probably about two months. The following is an 

 extract from Mr. Mien's interesting note* on this subject : 



" Simultaneously with the establishment of the experimental teak 

 plantations at Kulsi, Assam, there appeared an insect which may 

 yet cause considerable damage amongst the young teak, although up 

 to the present time its attacks have not been very serious, only a 

 small percentage of the trees having suffered, many of which recovered 

 partially or entirely. 



" The first symptom to be observed is the swelling just above the 

 ground, or sometimes a couple of feet up, of the stem, which is 

 occasionally of a considerable size. On close examination, small 

 punctures in the bark may be noticed, just beneath the swelling, 

 from which the excrements of the larvae exude. 



" After a hot day the young trees have a fading appearance, 

 though not invariably, and the leaves shrivel up. Frequently this 

 symptom is, however, not present, and the young tree remains appar- 

 ently vigorous until the larvae have bored their way so far into the 

 stem that the tree is snapped off by the wind. The globular swell- 

 ing is evidently the result of the efforts of Nature to repair the 

 damage, and is sometimes successful, insomuch that the tree 

 continues to live and thrive, though with diminished vigour. On 

 cutting over the stem, and slitting it carefully open so as to bisect 

 it longitudinally, the larva may be discovered a little above the 



* Note on the occurrence of the Teak Borer Beetle in Assam : Ind. For. iv, p. 347. 



