210 Dr. Wallace on 
born larva, the larva of B. Cynthia is not born till the end of June 
or the beginning of July, when the weather is warm and there is 
abundance of food. 
The larvae (see Pl. XVI.), when newly-born, are from } to +3 
of an inch long, and of a pale light yellow colour; but soon after 
feeding, a number of black spots and dark-coloured tubercles, ar- 
ranged in rings, become so conspicuous as to give the idea that 
the larvee are black with yellow rings; after the first moult the 
yellow ground becomes more manifest, and they attain a length of 
2 to 2 of an inch. Soon after the second moult they become grey- 
ish-white from the presence of a grey waxy powder secreted from 
the tubercles; the spots are a bluish-black; they now grow 
nearly to 1 inch in length. After the third moult the ground 
colour alters to a pale blue-green, with tubercles of the same 
colour; the spots, which are regularly arranged in four rows, 
remain of a bluish-black, while the head, feet and last segment 
are of a golden colour. After the fourth moult the larva has a 
length of 1} inch; the green colour becomes more intense, the 
extremities of the tubercles, the tips of the hind feet, the collar 
and parts of the last two segments become of a beautiful marine 
blue, while golden colour still adorns the head and hind claspers and 
the last two segments; the larva now eats enormously and attains 
a length of 3 inches to 34 and 4 inches when extended, with a 
thickness of 3 an inch. 
Now suppose the twelve days have elapsed and that to-morrow 
morning the eggs will hatch out,—how shall we best treat them ? 
Undoubtedly I believe even if the weather be wet and windy, it will 
be easiest for us and best for the larvae to put them over-night in 
little bags on the sheltered side of a sheltered tree as before de- 
scribed. If however we have not the means to do so, a similar 
plan may be adopted with a tree grown in a pot, and kept in a 
sunny window or a green-house: by so doing we avoid all trouble 
of feeding, and rear a larger per-centage of larvae. The next best 
plan will be in early morn to lay fresh-gathered leaflets, say three 
or four attached to their piece of leaf-stalk, lightly over the newly- 
born worms ; they will soon craw] on to this, and may be then car- 
ried and pinned through the leaf-stalk toa neighbouring tree. But 
if there are no trees to feed them on, then in all probability a much 
larger per-centage of young larve will die, as moist succulent food 
seems a necessity for them in their early life, and if treated as 
are the mulberry silkworms with leaves strewn over them, they will 
crawl on them, but wither away and dry up with the withering of the 
leaf, and from 90 to 95 per cent. will most surely die. Clearly 
