378 
Sandal-Wood-Boring Insects of Madras. 
References have been made at various times to the damage 
done to the sandal-wood trees in Madras by wood-boring 
insects. In 1891, a considerable loss was experienced in 
Mysore owing to their depredations, As is well known, the 
wood of this tree is particularly valuable, and when it is 
mentioned that the least blemish (and the old gallery of a wood- 
boring insect is considered a very serious one) reduces its 
value from ist class (R850 per ton) to 3rd (on R750) or 
4th (R700) or lower, it will be readily understood that it is of 
the first importance to know something about the life-histories 
of these insects and what measures are feasible to counteract 
their attacks. 
The insect which up to the present has been quoted as 
chiefly responsible for these attacks! is the caterpillar of the 
moth Zeusera coffez, Neitner, a species which also infests the 
coffee. Careful. observations on the ground have shown me 
that this belief is erroneous. Such species as have been sent 
to the Indian Museum for identification of the pest have been 
naturally small, and consisted probably entirely of branch-wood 
or small tops. These are the parts of the trees which the cater- 
pillars of the Zeuzera prefer. It is, however, the heart-wood of 
the main stem and the large branches that is of commercial value, 
and this is attacked by quite a different class of borer, It isa 
beetle grub belonging to the family Cerambyctdz, which contains 
some of the largest wood-boring insect grubs known, I 
can find no account of these having ever been reported as 
damaging the wood, and yet they are undoubtedly the main cause 
of the loss experienced. One specimen of yet another class 
of borer, the sirex already described on p. 337, was found in the 
heart-woed of a tree. These borers were taken in the North 
Coimbatore forests. 
Os 
1[ndian Museum Notes, Vol. III, 1, 1. 
