FAMILY PLATYPODIDAE 619 



North-West India make use of oak timber to a great extent it becomes 

 of the first importance to have a working acquaintance with the wood- 

 borers of the tree. 



PLATYPUS. 



Platypus biformis, Chap. 

 (The Chir Pine Platypid Borer.} 



REFERENCES. Stebbing, Jour. Bombay Nat. Hist. Society, vol. xviii, p. 19 (1907); id. wilmoti, Ind. For. 



Mem. Zool. ii, 36 (191 1). 



Habitat. North-West Himalaya. Also reported from Darjeeling (Coll. 

 Janson). 



Tree Attacked. Chir Pine (Finns longifolia). Jaunsar, Kumaun, Chamba. 



Beetle. Elongate, cylindrical, rufous brown, shining ; elytra slightly yellow-brown on 

 sutural area. Head broadly transversal, prominent, as wide as prothorax ; a median elevate 



longitudinal line on vertex, latter finely punctate ; front concave, 



Description. punctate-reticulate, with a median small circular depression or pit. 



Prothorax square, the median furrow terminated in front in an 



indistinct pit, followed by a median line ; near the anterior portion of furrow a small, finely 

 rugose patch, the rest irregularly rugose. Elytra striate-punctate, the first stria in the form of 

 a furrow, the intervals nearly smooth, the third widened basally, 2 and 5 with a basal tubercle, 

 all strongly and sparsely punctate, becoming tuberculate on the declivity, with a seta on each 

 tubercle. In the $ a small projection just above apex on each elytron. Under-surface 

 shining, punctate. Length, 5 mm. to 8 mm. The male and female beetles are shown in 

 pi. Ixiii. 



Larva. White and elongate, straight, with a well-developed head and prothoracic 

 segments ; abdominal segments tapering posteriorly. Length, \ in. 



This Platypus infests newly felled trees and also standing green ones. 



The insect in attacking a tree tunnels straight through 

 Life History. the bark into the sapwood, carrying its tunnel for an 



inch or so into this before going off at an angle ; 



from this latter point the gallery may have several sharp zig/ags in it, as 

 shown in fig. ib. When completed, or nearly complete, a male and female 

 beetle will be found in the tunnel, which is kept entirely free of wood-dust, 

 this latter being pushed up and ejected on the outer surface of the wood or 

 bark. As many as twenty or thirty eggs are laid by the beetle, and from them 

 hatch out minute white dots, the size of pins' heads, which ultimately grow 

 into small elongate larvae with yellowish heads. These larvae do not appear 

 to feed on the wood, but on a kind of fungus with which the tunnel bored 

 by the beetles is linnl. The life-cycle of this beetle is about six weeks from 

 egg to beetle, in the case of the autumn generation. Eggs laid about the 

 first to second week of October hatch out within a couple of days or so, and 

 the larvae are full-grown by the end of the month or first week in November. 

 The pupal stage is about two weeks, and the mature beetles issue about the 

 third week of the month should the weather prove favourable. I have not 

 been able to work out the complete number of life-cycles passed through in 



