174 14 _ INSECTA. - 
class of Insects. They are swathed or resemble mummies(1). 
Those of several Insects of this order, particularly of the 
Diurne, undergo their metamorphosis in a few days; they 
even frequently produce two generations in the course of the 
year. The caterpillars or chrysalides of others, however, 
remain during the winter in one of those states, and only 
appear as perfect Insects in the spring or summer of the fol- 
lowing year. Generally speaking, the eggs laid in the fall 
are not hatched till the ensuing spring. The Lepidoptera 
issue from their envelope in the usual manner, or through a 
slit which is effected on the back of the thorax. 
The intestine of caterpillars consists of a large tube without 
flexures, of which the anterior portion is sometimes slightly 
separated in the manner of a stomach, and the posterior forms 
‘a wrinkled cloaca; their four biliary vessels are very long 
and inserted very far back. 
In the perfect Insect, we find a first lateral stomach or crop, 
a second inflated or turgid stomach, anda tolerably long small 
intestine, with a cecum near the cloaca(2). 
The larve of the Ichneumonides and Chalcidites deliver 
us from a great portion of these destructive animals. 
We will divide this order into three families, which cor- 
respond to the three genera of which it is composed in the 
system of Linnzus. 
(1) The sheaths of the legs and antennz are fixed, a character peculiar to this 
sort of metamorphosis. 
(2) For the anatomy of the caterpillar, see the admirable work of Lyonet; and 
for the development of the organs in the chrysalis and butterfly, that of Herold, 
entitled History of the development of Butterflies, in German, Cassel and Marburg, 
1815. 
