240 AGRICULTURAL REPORT. 
the silk-worm disease, the pébrine, has recently been discovered in the 
eggs of the silk-worms of Japan, notwithstanding the distinct declara- 
tion of the Italian commission to the contrary. It first exhibits itself in 
the form of a corpuscle in the egg, and is said to be contagious and or- 
ganic, and capable of transmission by propagation. An examination 
of fifty cards being made by Lewis Crivelli, only six were found to be 
sound. The Italian congress called to investigate the subject came to 
the conclusion that the disease has its origin in this corpusele. The 
Japanese, therefore, have now to contend with this disease, and also with 
another, called the wi, besides an enfeebled state of the silk-worm, 
caused probably by the enormous demands for the eggs during a few 
years past. These difficulties are very formidable, and will require the 
most energetic efforts on the part of the silk-growers and the Japanese 
government to counteract them. The government has already distrib- 
uted throughout the silk districts Mr. Adams’s report on the wi, in which 
he deseribes how it fastens itself on the young worms, and deposits its 
eggs within their skins. He shows the necessity of destroying the wz 
at onee, instead of throwing it away as if a dead insect, when in reality 
it is a living one in the grub state. He recommends further that when 
silk-worms are about to spin their cocoons, the peasants should sepa- 
rate all those worms which, from the black mark on them, are known 
to contain wi,and suffocate all the cocoons which they produce, thus 
destroying the wi at the same time. ‘These cocoons would, of course, be 
used for silk. The home department of Japan has cailed the careful 
attention of the silk-producers to the various diseases to which the silk- 
worm is liable, and has demanded that they should search out the causes 
which produce them, instead of referring them to a supernatural power 
over which man has no control. It has also offered honorable mention 
and liberal rewards to those who will discover the best methods of eradi- 
cating the disease, or of improving the breed or the system of rearing 
the worms. It is cénfidently expected that these efforts of the govern- 
ment will result favorably in putting an end to these diseases, and 
bringing the silk production up to its original standard. 
It is supposed by some that the disease is caused by a small fiy which 
deposits its eggs on the silk-worm just before the latter enters the cocoon. 
These eggs, adhering to the worm, are carried into the cocoon, where they 
hatch about the time the cocoon is finished, producing very small mag- 
gots, which prey upon and destroy the chrysalis. | 
Dr. Tryski, the Austrian commissioner to Japan, visiting California 
on his way home, informed Mr. Hoag that the losses of cocoons set aside 
for eggs in Japan, in 1869, ranged from 30 to 75 per cent., the usual sup- 
ply of eggs being diminished in corresponding proportion. As a conse- 
quence, eggs commanded $4 50 to $5 per ounce; but notwithstanding 
this high price, there had been shipped to Europe, up to the time of nis 
leaving Japan, 1,300,000 ounces, at a cost in Japan of about $5,850,000, 
the shipment being stillin progress, and estimated to reach for the year 
2,000,000 ounces, at a cost of $9,000,000. He also stated that California 
had the power to secure this trade, for the reason that the disease men- 
tioned is extending its ravages in Japan, causing serious diminution in 
the supply of eggs and a corresponding increase in price. 
Professor Tyndall, in an address recently delivered in Liverpool be- 
fore the British Association, estimates that France has sustained a loss 
of $242,000,000 within the last seventeen years, caused by the pébrine, 
or silk-worm disease. 
M. Sintrae, of France, has made a series of experiments, which he has 
communicated to the Academy of Sciences in Paris, to ascertain the. 
