276 INSECTA, 
caterpillars are contented with connecting leaves, particles of earth, 
or of the substances on which they have lived, and thus forming a 
rude cocoon. The chrysalides of the Diurnal Lepidoptera, orna- 
mented with golden spots, whence the term chrysalis, are naked, and 
fixed by the posterior extremity of the body. The nymphs of the 
Lepidoptera present a special character, of which we have spoken in 
our general observations on the class of Insects. They are swathed 
or resemble mummies *.. Those of several Insects of this order, 
particularly of the Diurnz, 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 following year. Generally 
speaking, the eggs laid inthe 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 sepa- 
rated in the manner of a stomach, and the posterior forms a wrinkled 
cloaca; their four bihary 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, and a tolerably long small intes- 
tine, with a ceecum near the cloaca ft. 
The larvee of the Ichneumonides and Chalcidites deliver us from 
a great portion of these destructive animals. 
We will divide this order into three families, which correspond to 
the three genera of which it is composed in the system of Linnzeus. 
FAMILY I. 
DIURNA. 
f This family } is the only one in which the exterior margin of the 
inferior wings does not present a rigid, squamous seta or kind of 
bridle for retaining the two superior ones. These latter, and even 
Le aT. Lacan en Ll oo EEE Eee 
* The sheaths of the legs and antennz are fixed, a character peculiar to this sort 
of metamorphosis. 
+ 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 Butterflics, in German, Cassel and Marburg, 1815. 
+ Some of the Nocturna excepted. 
For the genera of the Diurnal Lepidoptera, see the first numbers of the Descrip- 
tive Catalogue of the Lepidoptera in the Museum of the East India Company, of 
M. Horsfield. 
