LEPIDOPTERA. 
95 
quickly commence to feed, while the keepers are always on the watch to protect 
them from insect-vermin, birds, etc., which, if permitted, would soon clear off* 
the whole plantation. Forty-live days at the outside, and the larvae are full-fed; 
they then spin their cocoons, pass into the pupa state, and the winding off of the 
silken harvest begins. The largest cocoons are selected and set aside for the 
breeding of larvae for another year. The rest are exposed to a high temperature 
which destroys the pupae within. Boiling water—in which the earthy salts of 
buckwheat ashes cleaned for this purpose have been dissolved—renders the cocoon 
lit for being unwound. The silk is wound off in strands,—live, six, or eight in 
number,—a single strand from each cocoon, according to the strength of thread 
required. The silk thus prepared is much stronger than that from the silk-worm 
moth, though it is neither so line in texture nor so valuable. The Japanese oak 
silk-moth (S. yama-mai) is closely allied to the above, and the process of culti¬ 
vation of the insect much the same. 
The Silk-Spinners,— Family Bombygibae. 
The only species belonging to this family known in Europe is the one 
mentioned above as the true silk-worm moth (Bombyx mori). This insect has 
become acclimatised in many parts of Southern Europe, where, as in China, it 
is cultivated for its silken produce. The larva is itself not remarkable, save 
perhaps for its resemblance to the caterpillars of the hawk-moths, with its smooth 
naked skin, and short erect tail. It is, however, by far the most valuable 
caterpillar yet discovered. Ages ago, from two to three thousand years before 
the Christian era,—if Chinese records be reliable,—this larva was well known in 
the far East, and already silk-culture was a well-established element in the 
national industry. History relates how the eggs were first brought to Europe, 
in the reign of the Emperor Justinian, by Persian monks, concealed in their 
hollow bamboo staves; and from these silk-culture in Europe took its origin. It 
was, at any rate, carried on at Constantinople in A.D. 520. The Arabs introduced 
the industry into Spain, whence it spread in the twelfth century to Sicily, and 
thence to Italy and all the south of Europe. So far as England is concerned, 
both James I. and George I. endeavoured to introduce the cultivation of the silk¬ 
worm for commercial purposes, but without success. The actual mode of cultiva¬ 
tion and preparation of the cocoon differs in no very essential feature from that 
of the oak silk-moth, save that it is usually conducted under cover in well- 
ventilated rooms; the wicker trays of silk-worms being arranged in rows one 
above the other on light bamboo racks. 
The Hawk-Moths,— Family SrmxGiDP. 
The large moths included in this family are either diurnal or subnocturnal 
in their habits, flying powerfully both in the daytime or just before nightfall. 
Amongst other characteristics, the antennie are gradually thickened towards the 
tip, which terminates in a hook. The fore-wings are elongate, narrow, and usually 
pointed towards the apex ; while the hind-wings are comparatively of small size. 
