THE MOTHS. 
4 % 
filk, did we know how to avail ourfelves of their labours. 
u. de Reaumur has meationed feveral wiiofe productions 
Ought to be fubje&ed to experiment bp the tmnufa&urer j 
snd in fome future period, fame of thel'c may be turned 
to account *. 
Of many of the caterpillars belonging to this clafs of 
infeils, the filk, it muft be allowed, is altogether unfit for 
our purpofes : their coques are not only coarfe, but fo 
fcantily provided with filk, that the animal is obliged to 
loin dry leaves, bits of wood, and other materials, in or- 
der to give (lability to its edifice : Farther, many of them 
fpin under ground, and their work conlilts only of join- 
ing and conne&ing together, by means of their threads, 
different particles of earth, of which their houfe is com- 
pofed. Thefe caterpillars, when kept by the naturalift, 
^ho waits For their phalamce, muft be fupplied with earth 
in the boxes in which they are lodged ; otherwife they 
will perilh, from not being able to conftruQ an edifice fit 
for their reception f. 
The phalaense, in their chryfalid (late, differ from the 
butterflies, in remaining for a much longer period before 
their metamorphofes into perfect inlefts is completed. 
Their form, too, is then different, being oblong, and not 
an gular, like the chryfalid of the butterfly. Some remain 
111 their coques for feveral years fucceffively ; efpecially 
**■ a cold damp (ituation has retarded their progrefs. So 
§ r eat is the effect of heat in precipitating their develo'pe- 
^ents, that a moth in a warm expofure may be produced 
from its chryfalid, even in the depth of winter. 
After the phalsenac iffue from their lad covering, fome 
them are deftitute of wings ; Thefe are the females of 
certain 
Tome I. Mew. ri. 
f Barbut’s Qeu. Infect, p. 1 89, 
