12 
Indian Forest Records . 
[Vol. VI 
worked out, but on tbe Asiatic species very little information bas been 
published. In another paper (Beeson, 1916, p. 219) the writer has 
pointed out that the gallery patterns of Indian species of ambrosia 
beetles of the families Platypodidae and Ipidae can be assigned to three 
general types ; and that the genera Platypus and Diapus exhibit gallery 
patterns of closely similar types, while the genus Crossotarsus is charac¬ 
terized by gallery systems constructed on a very different pattern. 
In a normally developed gallery system of Diapus furtivus, the 
entrance tunnel is carried horizontally * and more or less radially through 
the bark, beyond the cambium layer to a depth of \ an inch to 1 \ inches, 
according to the thickness of the sap-wood zone. The gallery then curves 
rather sharply to the right or left, or bifurcates in both directions, and 
the remainder of the system is continued,in a horizontal plane, in curves 
nearly coinciding with the increment rings. In branchwood or stems 
of small dimensions, the main gallery (Plate II, c) may be continued 
completely round the circumference, but in the bole of large trees, and 
where galleries are crowded, the work of several beetles in the same 
plane coalesces, and a somewhat intricate zone of tunnels forms a girdle 
to the heartwood. From the main gallery short branch galleries (Plate 
II, d) take off at a slight angle, and cease after reaching f of an inch 
in length, but are sometimes prolonged as secondary galleries running 
parallel to the main gallery for 2 or 3 inches. In addition to the 
secondary galleries there are several short bifurcate branches, which 
usually occur on the inner side of the main gallery and lie just within 
the heart-wood. Attached in a vertical plane above and below each 
of the arms of the bifurcate galleries, in close groups of 5 to 7, are small 
cells of f of an inch in length in which pupation of the larva takes place 
(Plate II, fig. e). 
Development of the Brood. 
On completion of the entrance tunnel, the first batch of eggs is laid 
in the tunnel and the female proceeds with the excavation of the main 
galleries, while the male remains at the entrance preparing the wax- 
tube. The eggs are left to hatch apparently without any special care 
by the parent beetles. Moreover, they are constantly shifted about, by 
the passage to and fro of the mother, while engaged in removing the 
particles of wood fibre resulting from the excavation of the main gallery. 
The female lays more eggs at intervals, until as many as 40 may have 
* In the description of the gallery pattern and elsewhere the terms “ horizontal and 
“ vertical” should be taken to mean at right angles and parallel respectively to the central 
axis of the tree, and thus may be applied equally to a standing or recumbent tree, 
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