MISCELLANEOUS ECONOMIC PRODUCTS 567 



RETURNS. It is estimated that under average conditions a yield 

 of 4 to 6 Ib. of stick lac per tree may be obtained. 88 Ib. "stick'' 

 will afford i cvvt. "seed lack." Seed or granular lac, produced 

 on Pithecolobium Saman in India, has been recently valued by 

 PROFESSOR DUNSTAX, Director of the Imperial Institute, at 55s. to 

 60s. per cvvt. "Ordinary" shellac is usually quoted in London at 

 45s. to 50s. per cwt., and "good soluble" or "fair spot" at 60s. to 70s. 



SERICULTURE 



As is well known, the production of silk is due to the "worms" 

 (caterpillars) of certain moths, which in some countries, as in 

 China, parts of Southern Europe and Northern Asia, are cultivated, 

 or rather bred, in enormous numbers in order to produce their 

 cocoons, which furnish the silk of commerce. The worms are 

 reared in light airy sheds, on tiers of trays, and fed by the leaves 

 of certain plants which they eat voraciously. There are several 

 species of silk-producing worms, the principal being the Mulberry 

 silk- worm (Bombyx Mori] which feeds chiefly on the Mulberry 

 leaves ; the Eri worm (Attacns ricini), which feeds on the Castor- 

 oil plant; and the Tussar worm (A ntheraea Pernyi), which feeds 

 chiefly on the Oak. The worm of the Atlas moth (Atlacus atlas), 

 which is common in Ceylon, also produces a good second-rate 

 silk and is omnivorous as regards its food. The Mulberry kind is 

 the most important and is the one grown so extensively in Europe ; 

 the Eri is much in favour in India, while the Tussar is produced 

 chiefly in China. The mulberry silk-worm yields the best 

 quality silk, and its mode of existence, like that of other silk-worms, 

 is briefly as follows. The moth lays its eggs, often to the number 

 of 500 or more, on a leaf or twig, to which they adhere by means 



