162 



INSECT TRANSFORMATIONS, 



respiration, like the gills of fish, though there are 

 several other spiracles in other parts of the body com- 

 municating with the large convoluted windpipes. 

 The anal apparatus is surrounded with five hard, 

 moveable, triangular pieces, all fringed with hairs, 

 which it can open or shut at pleasme. The largest 

 of these pieces is placed above, while the two smallest 

 stand at the sides, and two of the middle size below. 

 When they are shut close they form a blunt cone.* 



a, grub of a dragon fly; 6 b, the lody laid open and magnified, 

 to show the windpipes; <■, the pumping appaiatus shut; </, the 

 same ojjen; e, head of the insect. 



It may not be out of place to take notice here of 

 another singular structure in the same species of lar- 

 vae, which is probably unmatched in the insect world. 

 In the larvtB of most insects, the under-lip is small 

 and inconspicuous, but in those of the dragon-flies, 



* De Geer, ii, 666, and Reaumur, vi, 3f>3, &c. 



