6i4 



FAMILY PLATYPODIDAE 



The mature beetle is to be found boring into fresh deodar wood towards 

 the end of June at elevations of from 6,000 ft. to 7,000 ft. 



Life History. The beetle bores down through the bark, making a 



cylindrical tunnel straight into the sapwood, this 

 portion of the tunnel being either carried vertically downwards (in case of 

 felled trees) or at an angle, perhaps more often the latter. When she has 

 got down from half an inch to an inch into the sapwood the female is joined 

 by a male beetle. This latter may have entered by crawling down the 

 female tunnel, or he may bore a separate tunnel to intersect the female 

 tunnel in the sapwood. Pairing takes place here. From this point the 

 female subsequently takes her tunnel for an inch or so at an angle to the 

 previous direction, and then zigzags in another direction until she has 

 attained the required distance down into the wood. She then turns and 

 eats out the remaining portion or branch of the tunnel in a direction usually 

 more or less parallel to the outer bark, and at right angles to the long axis 

 of the tree. This part of the tunnel is about 2 in. in length, is quite straight, 

 and has no enlargement at the bottom (pi. Ixii). Close to the end she 

 deposits her first eggs. The number of eggs laid altogether b\' the beetle 

 has not yet been ascertained, but in igog I found a little mass of four 

 freshly laid eggs adhering 

 together near the bottom 

 of the tunnel with the 

 female beetle a little higher 

 up. The eggs are not stuck 

 together by any adhesive 

 matter, for the ones taken 

 were found to be quite 

 separate and easily parted 

 on drying. 



Only a few young 

 larvae have as }et been 

 taken in these tunnels. 

 They do not feed upon 

 the wood, but probably belong to the so-termed "'ambrosia" beetles, 

 feeding upon fungous matters, either growths on the walls of the tunnel 

 from the fresh sap which exudes down the walls, or perhaps induced 

 there by the beetle itself, at any rate at first during the young stages of 

 growth of the larvae. That this latter may be the case the habit of the 

 beetle in remaining alive in the tunnel and moving up and down it during 

 a considerable portion of the period required by the larvae in reaching 

 full growth would seem to support. On the other hand, the wet sappy 

 state in which the walls of the lower or inner part of the tunnel are 

 always to be found, and the depth to which the female takes the portion of 

 the tunnel in which she lays her eggs, where the walls remain moist for a 

 period sufficiently long to enable the grubs to reach their full growth, would 



Fig. 389. — Egg-tunnel idiagrammatio with eggs and female 

 beetle of Crossotarsns coni/erae, Steb., in deodar \\ood. 

 Chamba, N.W. Himalaya. (E. P. S.) 



