Silkworm from Japan. 359 
delmaatchappij, and was divided between M. de Graf and M. de 
Weckherli, Secretary to the Queen of the Netherlands. A third 
portion I offered to my own government, and His Excellency the 
Minister of the Interior transmitted them to the Dutch Entomo- 
logical Society. Lastly, there remained a few more eggs, which I 
handed over to the celebrated naturalist Dr. Bleeker, who had 
asked for them for Mons. Guérin- Méneville.” 
From this beginning the new species spread over Europe. In 
1865 and 1866 several trials were made in England to rear the 
species ; but, I believe, all have been unsuccessful.* The same 
want of success has attended many trials in France, Holland, and 
other countries ; but still several gentlemen have attained success 
even ona large scale. Thus, Mons. Guérin-Méneville, at the Im- 
perial farm at Vincennes, on a small scale, and Mons. Chavannes, 
Professor of Zoology at the Academy of Lausanne, and Mons. 
Personnat, at Laval, France, have succeeded in rearing thousands 
of cocoons. Let us hope therefore that in England this Bombyx 
may speedily be successfully cultivated; and [trust that, in writ- 
ing this Essay, and collecting all that is known about this 
beautiful but delicate insect, 1 may hasten the day when these 
valuable cocoons may be grown ona large and remunerative scale 
in Our own country. 
In describing this Bombyx I propose to commence with the 
egg stage, not only as being the first era in the life of the insect, 
but also because it differs from the Ailanthus silkworm, B. Cynthia, 
and resembles the mulberry worm, B, Mori, in passing the winter 
in the egg state: so that the year commences with the egg 
state, whereas in B. Cynthia the perfect insect first makes its 
appearance in the early summer, after passing the winter in the 
cocoon stage. 
The egg of the Yamamai is large and spheroidal; but, in 
consequence of the changes that take place within, it often 
is slightly concave on the upper and under surfaces. _ Its 
greatest diameter is from 4—-)5 of an inch; its smallest, 
!s—-z of an inch. The shell is of a pale straw-pink colour 
naturally, but is thickly coated over with a tenacious brown 
gum, which gives it a mottled or marbled dark brown look. The 
shell appears covered with a number of fine punctations exter- 
nally, which are doubtless pores, in order to permit the entrance 
* Two males, as I am informed, were reared in 1866, at York, by Mr. 
Dossor, one from a cocoon sent him by Capt. Porrett; and two moths were 
reared by some schoolboys, one at Louth, and the other at Wootton-under- 
Edge. 
