STATES OF INSECTS. 205 



food, by a copious evacuation they empty the intestinal 

 canal, even rejecting the membrane that lines it and the 

 stomach a ; their colours either change totally, or fade ; 

 and they make themselves ready for entering upon a 

 new stage of their existence. Some merely rest in a 

 state of inactivity in the midst of the substances in which 

 they feed, as if conscious of their inability to select any 

 safer abode. Of this description are most Coleopterous, 

 Hymenopterous, and Dipterous larvae, that feed under 

 ground, or in the interior of trees, fruits, and seeds. 



But a still larger tribe, those which feed on leaves, ani- 

 mals, &c. act as if more sensible of the insecurity of this 

 to them important epoch. They are about to exchange 

 their state of vigour and activity for a long period of death- 

 like sleep. The vigilant caution which was wont to guard 

 them from the attack of their enemies will be hencefor- 

 ward of no avail. Destitute of all the means of active 

 defence, their only chance of safety during their often 

 protracted night of torpor must arise from the privacy of 

 their place of repose. About this, therefore, they exhibit 

 the greatest anxiety. Many, after wandering about as if 



a A caterpillar nearly answering to the description of that of 

 Bombyx camelina, which I found upon the hazel, after a few days 

 produced sixteen grubs of some Ichneumon. At first these grubs were 

 green, but they became gradually paler ; and after a day or two be- 

 came pupae. But I mention this circumstance here for another rea- 

 son : upon examining them after this last occurrence, I observed that 

 they adhered to the lid of the box in which I kept the larva, arranged 

 somewhat circularly ; and at a little distance from the anus of each 

 was a pea-green mass, consisting of about eight oval granules, which 

 appeared like so many minute eggs. These were the excrement eva- 

 cuated by each grub previously to its becoming a pupa. The appear- 

 ance of this little group, with their verdant appendage, formed a cu- 

 rious spectacle : they are still pupa?, July 30, I82g. 



