148 SCIENCE

report to the Senate. "Whence does it come? how
is it contracted? No one knows. But its invasion
is recognized by little brown or black spots." It
was therefore called "corpuscle disease"; it was
also designated as ffgat tine" from the Italian
gaitinc, kitten; the sick worms held up their
heads and put out their hooked feet like cats
about to scratch. But of all those names, that of
"pebrine" adopted by Quatrefages was the most
general. It came from the patois word pebre
(pepper). The spots on the diseased worms were,
in fact, rather like pepper grains.

The first symptoms had been noticed by some
in 1845, by others in 1847. But in 1849 it was a
disaster. The South of France was invaded. In
1853, seed had to be procured from Lombardy.
After one successful year the same disappoint-
ments recurred. Italy was attacked, also Spain
and Austria. Seed was procured from Greece>
(Turkey, the Caucasus, but the evil was still on
the increase; China itself was attacked, and, in
1864, it was only in Japan that healthy seed
could be found.

Every hypothesis was suggested, atmospheric
conditions, degeneration of the race of silkworms,
disease of the mulberry tree, etc.—books and
treatises abounded, but in vain.

When Pasteur started for Alais (June 16,
1865), entrusted with this scientific mission by
the Minister of Agriculture, his mind saw but