FAMILY CERAMBYCIDAE 353 



posterior coxae and then gradually constricted to apex, latter broadly truncate ; surface dull, 

 rugose. Under-surface rather densely pubescent, the pubescence greyish, densely clothing the 

 thoracic parts and forming bands on the posterior halves of the abdominal segments. Legs 

 black, pubescent ; hind femora extend by about one-fifth their length beyond apex of elytra. 

 Length, 15.2111111. : breadth, 3.7mm. 



Little appears to be known on the subject of the life history of this 



insect. I took a specimen ovipositing on a branch of 

 Life History. a rubber plant some ten feet in height in the nursery at 



the Charduar Rubber Plantation on 10 April 1906. 

 The beetle was clinging to a branch, and I watched two eggs laid. The 

 eggs are small, semi-elliptical, semi-globular, translucent bodies. 



Xylotrechus sp. 



Habitat. Sal ween River, Tenasserim. 



Tree Attacked. Terminalia tomentosa. Wutgyi, Sahveen River, Tenas- 

 serim. 



Beetle. Elongate ; lightish brown with pale white markings ; prothorax with sides angled 

 medianly ; elytra not wider than prothorax at base. Pygidium exposed, pointed ; legs very long. 

 Owing to immersion in bad spirit the beetles were in too poor a state of preservation to enable 

 them to be identified. 



Larva. Yellowish white in col6ur, fairly stout and .thick, short, with a rather well- 

 developed head and thoracic segments. Blunt posteriorly. 



Pupa. Whitish yellow in colour. Has the ordinary appearance of a longicorn pupa. 

 The beetle first appears on the wing in the early part of March, and 

 continues issuing throughout the month in Tenasserim. 

 Life History. All stages of the insect larva, pupa, and beetle were 

 taken in a felled green tree, the tree having been cut 

 early in the past cold weather, probably in November or early in December. 

 Others were subsequently taken from a standing, nearly dead tree. 

 The egg is laid in an interstice of the bark of the tree. The young larva 

 on hatching feeds at first in the cambium layer, and then in this and the 

 sapwood, hollowing out a widening tunnel which grooves both. This 

 tunnel is packed with the excreta of larva and wood-dust. When full-fed 

 the grub bores vertically down into the sapwood (or at a slight angle) for 

 about half an inch to an inch, and then eats out a small narrow chamber 

 of about its own length in the sapwood parallel to the long axis of the 

 tree. This tunnel is about three-quarters of an inch in length, and the 

 larva pupates in this. In some of these chambers mature beetles were 

 found on 7 March 1905. Others had already left and were probably ovi- 

 positing in fresh trees in the forest. This generation would appear 

 to take about five months to pass from egg to beetle. There are con- 

 sequently probably at least two life-cycles in the year. 



The beetle was in large numbers in the felled tree examined, and a 

 large portion of the cambium had been removed from 



iL When the inSGCt infeStS treCS in numbers il: is 

 quite capable of ringing the stem by removing the 



bast and consequently killing the tree. 



9003 Z 



