158 THE OAK SILKWORM OF CHINA. 
It is difficult enough to extract good information from Chinese when 
in the midst of the things inquired of : at a distance it is next to im- 
possible. As an instance of this, I may state that in spite of all my frequent 
inquiries made both when in the silk-producing district and at this port 
from natives of that district, it is only within the last few months that I 
have learnt of another tree besides the oak on which the large worm feeds. 
The oak bush is called locally Po lih ko tsi. The other bush is called 
Chien tso tsi. Its leaves are narrow and long as compared with those of 
the oak bush. Its bark is of a greenish white hue and is smooth, and 
its trunk and branches straight and ungnarled as compared with those of 
the oak. It produces a seed or fruit on which pigs feed. It must, I 
think, be a species of beech. The silk produced by worms fed exclu- 
sively on this bush is said to be stronger than when they are fed on the 
oak. 
It is, I fear, beyond doubt that the oak leaf-eating worm, the shan keen 
or mountain worm, as the Chinese here call it, is of a different species 
from the mulberry leaf-eater, which is here called the kea keen or do- 
mestic worm ; and that, therefore, the hope hinted at by Mr. Major, of 
a beneficial crossing, cannot be indulged in. On the other hand, the 
mulberry leaf-eater or domestic worm of the New-chwang Consular dis- 
trict does seem to be of the same species as that of middle China ; and 
it might be desirable to try the effects of a crossing with an insect that 
has probably for many generations been a separate inhabitant of this 
widely different climate. 
As the cocoon produced by the mountain worm is about three times 
the size of that produced by the domestic worm, so the worm itself is 
about thrice the thickness, though little if anything longer. It is of a 
brown or dry earth colour, and has on its back little knobs or pro- 
tuberances. In its flying stage the "mountain" insect is a large and 
richly coloured butterfly, measuring from tip to tip of its expanded 
wings some seven to nine inches, " as large as a swallow." A native of 
the silk country now here professes to have once fed a few mountain 
worms on mulberry leaves. They ate as much as five or six times the 
number of domestic worms : and the cocoons they spun did not at all 
differ in their appearance from those spun by mountain worms fed on 
oak bushes. The same man tells me that the stuff made from the cocoon 
of the mountain worm will take only a black or a purple dye, and that 
those who desire to make with it a stuff of other colour are obliged to 
i se some proportion of cotton threads. 
Looking to the three great classes of textiles, cotton, wool, and silk, 
the produce of the mountain worm must be classed with the latter, inas- 
much as it neither grows on a shrub nor on an animal's back, but is 
produced by a leaf-eating worm, and viewed as " silk," it is manifestly 
of an inferior quality. But if we choose to look at it simply as a new 
textile, there is some reason to believe that it may prove to have useful 
qualities not possessed by either silk, wool, or cotton. 
