HYPOBORUS (?) SP. 279 

out a small circular or irregulareshaped chamber in the bast and 
wood [see Pl. XVII, fig. 2, c (p)]. The 2 beetles enter by the 
same hole and are fertilized by the @. At this stage four beetles 
will be found in the chamber beneath the bark, and it is prob- 
able that the gtheretore fertilizes at least three females. After 
pairing the female beetles do not apparently bore any definite 
egg gallery away from the pairing chamber but merely enlarge 
this by eating out the bast and sapwood on one side, laying eggs 
in the portion so treated. The whole of the large irregular 
gallery thus made by the beetles, which often completely encircles 
the stem beneath the bark, thus effectually girdling the branch 
is filled with the moist chewed and passed wood refuse and 
excreta which fill it entirely and amongst which the eggs are 
evidently laid. The pairing chamber (p) in the figure shows 
this. The egg stage is evidently a very short one, probably 
a day or two only, since I have often found young larve in 
the chamber amongst the beetles and wood-dust. The larve 
bore away from the central chamber, either up or down 
the stem, their galleries being blocked up with wood-dust and 
excreta, fig. 3, b (2). When full-fed they hollow out at the end 
of the gallery a largish chamber in the sapwood and pupate 
in it [fig. 3, b (m)]. When boring their egg-chambers, the 
beetles commence work in opposite angles of the pairing cavity. 
The first beetle to enter the branch generally does so just below 
the juncture of two branches, In the subsequent boring opera- 
tions the branch is often completely girdled below the fork, the 
chamber being extended up one or both of the arms above it. 
This insect is to be found boring into deodar branches in 
the first week in June, and the beetles evidently take some time 
over egg-laying since the first developed larvz are to be found 
in the chambers whilst the beetles are still at work. It is not 
yet known whether this is the first or second generation of the 
year. Ihere is evidently a later one, as on October 24th I ob- 
tained some nearly mature beetles from girdled deodar branches 
collected in the Jaunsar Division at the end of June. These 
beetles had evidently matured from the larve hatching from 
the June eggs. These October beetles hibernate through the 
winter in this state. U 
