2 
Indian Forest Records. 
[ VoL. I. 
CHAPTER I. 
ORIGIN AND NATURE OF LAC. 
Lac is a resinous incrustation excreted by a scale insect kno\vn as 
Tachardia lacca. The mouth parts of this insect consist of a ‘ beak ’ 
or sucking apparatus combined with a pointed lancet. With this latter 
the scale pierces the bark of the twig of the tree and then inserts the 
sucking tube and draws up the sap. The insect may be likened to an 
animated siphon, since the sap continually sucked up through the beak 
is, after modification and absorption of some of its products, given out 
as an excretion at the anal end of the body. This excretion solidifies 
on contact with the air and thus there is gradually formed round the body 
a ‘ scale ’ or ‘ cell ’. This scale or cell is popularly known as lac. Were 
only a single insect present on a branch the scale would appear as a cir- 
cular dome-shaped reddish excrescence on the surface of the bark. Owing, 
however, to the production by the female of a very large number of eggs 
(as many as 1,000) and the habit of the insects, which indeed is common 
to many of the family, of living and feeding gregariously closely packed 
together on one twig, the scales or cells coalesce during their formation 
and result in the production of a continuous incrustation on the twigs 
which, on collection, forms the article of commerce known as stick-lac. 
From this stick-lac the product known as ‘ shellac ’ is manufactured. 
There is a second substance obtainable from the scales and known to com. 
merce as lac-dye for which formerly there was a considerable demand — 
a demand which, owing to the introduction of synthetic dyes, has practi- 
cally disappeared. As will be shown later, this product consists for the 
most part of the material from which the eggs are developed in the body 
of the female insect. There is still a small export of this lac-dye from 
India, but as will be seen from the table at the end of this monograph 
(Chapter XV) the total value for the whole of India is extremely small. 
CHAPTER II. 
HISTORICAL. 
The lac industry is amongst the most ancient of the minor industries 
of India. The trees far excellence upon which the insect lives are the 
