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Rh 27.23 pounds of raw silk per acre of mulberries, and this would require a mean yield of 4465 pounds of green mulberry leaves per acre, at the rate of 164 pounds per pound of silk.

Fig. 187.—Selecting the best cocoons, male and female determined by the shape and size, for purposes of breeding.

Ordinary silk in these countries is produced largely from three varieties of mulberries, and from them there may be three pickings of leaves for the rearing of a spring, summer and autumn crop of silk. We learned at the Nagoya Experiment Station, Japan, that there good spring yields of mulberry leaves are at the rate of 400 kan, the second crop, 150 kan, and the third crop, 250 kan per tan, making a total yield of over thirteen tons of green leaves per acre. This, however, seems to be materially higher than the average for the Empire.

In Fig. 188 is a near view of a mulberry orchard in Chekiang province, which has been very heavily fertilized with canal mud, and which was at the stage for cutting the leaves to feed the first crop of silkworms. A bundle of cut limbs is in the crotch of the front tree in the view.