INTRODUCTION. 79 



1. The Iidiform or pre-eminently typical, which 

 are smooth and destitute of horns or other excres- 

 cences; for example, the caterpillars of cabbage 

 butterflies. 2. Raptorial, or sub-typical. These 

 are the type of evil, having the body covered with 

 pungent spines, &c. ; for example, the caterpillar of 

 the peacock butterfly. 3. Natatorial or Anopluri- 

 form ; caterpillars of the Hesperidae, and Hawk- 

 moths. 4. The Suctorial or Vermiform, called also 

 the Onisciform; example, caterpillars of Polyom- 

 matus. 5. Rasorial or Thysanuriform ; head and 

 tail armed with spines ; for example, the caterpillar 

 of Pap. Cassia?. 



However much deserving of commendation cer- 

 tain parts of these classifications may be, they are 

 far from being satisfactory on the whole. In a race 

 of insects having the parts of the mouth, which 

 afford such valuable characters in most other groups, 

 so similar to each other, it can only be by a judi- 

 cious combination of characters derived from all 

 the different states, and not from one of them 

 only, that a proper arrangement can be effected. 

 The state of our knowledge is not at present such 

 as to render an attempt of the kind advisable. A 

 long and careful investigation of larvae in their native 

 haunts, — a more diligent search than has yet been 

 made for the perfect insects, particularly of the 

 smaller kinds, in foreign countries, must previously 

 be undertaken. In scarcely any other department 

 of exotic entomology has so little progress been 

 made as in this. This has been partly owing to the 



