24 
to separate them, or that the original colour of the worm had been dark, and an effort 
was being made to revert from a sickly condition to the original healthy starting-point. 
He accordingly picked out all the dark-coloured worms and reared them separately, 
allowing the moths to couple only inter se, and the same with the white worms. In 
the following spring the one batch of eggs produced nearly all dark brindled worms, 
whilst the other batch produced white worms, sparingly interspersed with an occasional 
dark one; these latter were removed into the dark batch, which was also weeded of its 
pale worms. In the third year the worms were still darker than before, and were 
always larger and more vigorous than the pale ones, giving larger and better-stuffed 
cocoons. Just as the eggs of the third year had been collected, a violent gale of wind 
upset the whole, but in the spring of 1862 the author recommenced de novo, and went 
over the same ground again. The few dark worms picked out escaped disease 
altogether, though reared in the same manner, in the same room, in the same 
temperature, on the same quality of food as, and in close contiguity with the others. 
In due time they spun cocoons, and produced moths, which, coupling inter se, 
deposited a fair stock of eggs, with which the experiments were continued in 1863. 
The eggs began to hatch on the 16th of March, and no sign of disease was apparent 
until the moths came forth, when many still showed defects in the malformation and 
dark spotting of the wings. As compared, however, with the previous year there was 
decided improvement; still there were too many white worms in the brood, but there 
was no symptoms of disease, the worms attained a larger size by a quarter of an inch 
and produced larger cocoous, and the moths laid good-sized eggs, great numbers of 
which adhered firmly to the paper upon which they were deposited, and many of the 
male moths displayed unusual vigour in flying in search of the females. Bat still 
more extraordinary was the fact that some of the eggs of Bombyx Mori of the spring 
crop of 1863 began to hatch again for a second crop on the 7th of August; these were 
all of the dark stock. The hatching continued throughout August, and occasionally 
‘even to the 23rd of September, when, through fear that the supply of leaves might fail, 
the eggs were removed to a temperature below 70° Fahr., in order to check the 
hatching. The worms which were then hatched throve and spun good cocoons, 
superior in size to those of the spring crop; in due time the moths appeared and were 
fully twice as large as those of the spring, depositing large well-formed eggs. In the 
beginning of December, to the author's dismay, more worms were hatched from the 
spring batch, and they continued to come forth at the rate of forty or fifty daily in a 
temperature of 53° Fahr., until, there being no more leaves upon the trees, the 
remaining eggs were placed in the open air at night, in order that the hoar frost 
might put a stop to further hatching. The whole of these worms were of the dark 
kind, and no white ones appeared amongst them as in the spring. This circumstance, 
so unusual with Bombyx Mori, the author attributed entirely to an accession of 
health and strength in the black worms; he regarded the occasional occurrence of the 
dark form in domestication as an attempted return on the part of Nature to the 
original colours and characteristics of the species, and considered the whiteness of the 
generality of the worms as a positive indication and proof of the destruction of the 
original constitution; in fact, the dark worms were the original and natural worms. 
This conclusion was further supported by arguments deduced from the strong 
similarity in the disposition and arrangement of the markings to those of the existing 
wild races in India, and by analogy to the general fading in domestic stocks of the 
original colour, to give place to piebald and finally to white. The author had long 
