north, is it not reasonable to inquire whether each individual species may 

 not originally in its native climate have been furnished with some 

 particular tree upon which it throve better than upon others ? It must at 

 least be evident that the annuals of the north could not have been nourished 

 upon trees that are peculiar to the south, and vice versd. To feed the northern 

 worm upon the finer leaf of the southern tree would be nothing better than a 

 silly attempt to destroy its constitution by slow starvation. 



That some leaves are preferred to others every cultivator must have seen, 

 and during my experiments to restore the health of B. mori, I often found 

 that although sometimes when pinched by hunger some of the multivoltines 

 would sparingly eat of the leaves of the coarse wild mulberry of the hills, 

 yet on the supply being intermixed with the leaves of the China mulberry 

 \Morus Sinensis), the former were at once abandoned for the latter; while as 

 to B. mori, although a northern species, it would never touch the wild leaf at 

 all. Nor does the above opinion appear to be wholly unsupported by facts, 

 for the wild silkworm (B. Huttoni) of the north-western Himalaya must 

 have been wholly restricted to the coarse leaves of the indigenous trees pre- 

 vious to the introduction of the cultivated Chinese plants, and indeed in 

 many parts of the hills they are so still. That they readily eat the leaves 

 of other mulberry trees is nothing to the purpose, the question being, did 

 nature restrict them to any particular tree ? The answer being undoubtedly 

 she did, until man interfered to upset the arrangement. Another point to 

 be considered in the rearing of northern worms upon southern leaves is the 

 fact that, from their thinness, twice or thrice the quantity will be required 

 to properly nourish the worm, and this increases the outlay ; besides which, 

 the longer the time consumed in feeding, the less repose does the insect 

 receive, and this is injurious to its well-being. 



But supposing, as is most probably the case, that the leaves of imported 

 trees in an uncongenial climate are deficient in proper nourishing con- 

 stituents, the worms and consequently the crop^of silk must likewise be 

 affected, and the very same thing arises from the injudicious method prac- 

 tised in Bengal of constantly cutting down the bushes for the nourishment 

 of the worm ; for in such cases the leaves are wholly immature, watery, and 

 poor, and therefore do not furnish the worm with the necessary constituents 

 for producing good silk, while the quantity must likewise be reduced. 

 Doubtless the natives will tell us that this is the cheapest method and they 

 can afford no other, and this may be true, but the purchaser of cocoons should 

 be wiser in his generation and remember that as veal is not beef so in like 

 manner are young mulberry shoots inferior as an article of food to the 

 mature leaf. The niggardly policy that would put every shilling into the 

 pockets of the cultivators and bestow nothing upon the worm and its 

 produce, is the very worst that could be adopted, and is decidedly one of 

 those causes which have hitherto led to such lamentable and disastrous 

 results. A thorough revision and alteration of the prevailing system is 

 absolutely necessary, and if the purchaser of cocoons does not strenuously 

 endeavour to repair the mischief which is manifested in the failing constitu- 

 tion of the multivoltines of Bengal, he will soon have reason to bewail his 

 negligence. 



Now it appears to me that the great number of mulberry feeding silk 

 worms now known to exist, amply warrants the conclusion that a corres- 

 ponding variety of trees has been furnished for their nourishment, each 

 probably being modified to suit the climate and other conditions under which 

 the worms themselves may have originally existed. Some perhaps may 

 have been restricted to one species only, while others may have had a wider 

 range, for had not something of this kind been intended why has such a 

 variety of mulberry species been created ? If all worms throve equally well 

 upon the same species of tree in every climate in which indigenous, why 

 create such a number of other species, many of which probably differ in 



