MOTIONS OF INSECTS. 291 



way — always walks backwards, even when its legs are 

 cut off. 



The jumpers amongst pedate larvffi, as far as they 

 are known, are not very numerous, and will not de- 

 tain you long-. When the caterpillar of Noctua Qua- 

 dra, F., a moth not uncommon, would descend from 

 one branch or leap to another, it approaches to the 

 edge of the leaf on which it is stationed, bends its body 

 together, and retiring a little backwards, as if to take 

 a good situation, leaps through the air, and however 

 high the jump, alights on its legs like a cat. That of 

 another moth {Pi/ralis roslralis, F.) will also leap to a 

 considerable height. 



Another species of motion, which is peculiar to 

 larva, — their mode I mean of climbing, — as it merits 

 particular attention, will occupy more time. I have 

 already related so many extraordinary facts in their 

 history, that I promise myself you will not disbelieve me 

 if I assert that insects either use ladders for this purpose, 

 or a single rope. You may often have seen the cater- 

 pillar of the common cabbage-butterfly climbing up 

 the walls of your house, and even over the glass of 

 your windows. When next you witness this last cir- 

 cumstance, if you observe closely the square upon 

 which the animal is travelling, you will find that, like 

 a snail, it leaves a visible track behind it. Examine 

 this with your microscope, and you will see that it con- 

 sists of little silken threads, which it has spun in a 

 zigzag direction, forming a rope-ladder, by which it 

 ascends a surface it could not otherwise adhere to. 

 The silk as it comes from the spinners is a guraroy 



» Uostl, 1. iv. U2. vi. ii. 



U 2 



