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~I 
THE GENUS PISSODES AND ITS IMPORTANCE IN FORESTRY. 
GENERAL ACCOUNT OF THE GENUS PISSODES. 
The species belonging to this genus have a longish rostrum. 
Near the middle of the rostrum the elbowed antenne are inserted, 
their long basal joint almost reaching the small, slightly projecting 
eyes. The prothorax! is narrowed in front, and its posterior 
margin, on examination with a lens, may show two slight excava- 
tions. The scutellum? is round and raised. The elytra® quite 
cover the abdomen. Femur untoothed, tibia straight, and with a 
strong curved hook at the point. The third joint of the tarsus 
is broad and two-lobed, and the terminal fifth joint ends in two 
simple claws. 
Rounp oF Lire. 
In round of life most of the Pissodes agree. The females lay 
their eggs in the bark of needle-leaved trees, a varying number of 
eggs being laid in each bore-hole. The hatched out grubs, 
starting from a common centre, gnaw long winding tunnels in 
the bark, the tunnels increasing in size with the growth of the 
larvee, the whole, it may be, showing a ray-like pattern. This 
ray-like design is not so frequently met with in Pissodes puniphilus 
or in Pissodes notatus, The full-fed larve having reached the 
innermost layers of the bark, gnaw in the outermost layers of the 
wood a kind of little bed or cradle, oval in shape, and here, 
covered by a cushion of sawdust and chips, they pupate. The 
mature beetles, when ready to escape, bite a clean-cut circular 
hole through pupa-bedcover and bark. 
The grubs living between the bark and the wood interfere 
with sap-circulation, and the infested plants or trees sicken 
and die. 
The question, so often debated among forest entomologists, as to 
whether this species or that will attack a healthy tree is men- 
tioned by Altum in relation to the Pissodes, which he writes of as 
preferring feeble and unhealthy trees to healthy and well-grown 
ones, his experience showing him that where old timber had been 
attacked the tree had certainly previously been weakly. At the 
1 Prothorax—the segment bearing the front pair of legs. 
2 Scutellum—the segment bearing the second pair of legs is called the 
mesothorax ; what can be seen of its upper surface in these beetles is called 
the scutellum. 
3 Elytra—the horny covers underneath which are the wings used in flight. 
