106 NATURAL ARRANGE3IENT OF INSECTS. 



small size of the head : this part projects so little be- 

 yond the thorax., that, in the typical species, it would 

 scarcely he perceived, but for the broad and highly 

 pectinated antennae, most conspicuous in the male sex : 

 the palpi are very minute, hairy, and lie close to the 

 head ; while the wings are broad, large, and ornamented, 

 in all the typical examples, with transparent ocellate 

 spots. 



(104.) The natural divisions of the Bombycides are 

 completely unknown ; but as, for the purpose of refer- 

 ence, and the more easy detection of species, it is es- 

 sential to make some rude assortment of the genera, we 

 shall place them under the following heads, until a 

 better acquaintance with the whole has been obtained 

 by analysis : 1. Hepialidce, or ghost moths; 2. Bom- 

 bycidce, or silk spinners ; 3. Arctiadce, or tiger moths ; 4. 

 LithosiadcB, or day-moths ; 5. Cryptophasidce, or hermit 

 moths. 



(105.) These divisions maybe thus slightly character- 

 ized. The first are chiefly composed of large, full-bodied 

 insects, with long narrow wings ; and feed, during the 

 caterpillar state, within the trunks of trees. The larva 

 is either entirely naked, or thinly covered with scat- 

 tered hairs. The second, or true silk worms, has been 

 already noticed: the larva is generally covered with 

 stellate tufts of short hairs, very stiff, and sometimes en- 

 dowed with a poisonous, or, at least, a highly irritating 

 quality. The third comprises all those usually deno- 

 minated tiger moths, from the black spots which orna- 

 ment their red or orange under wings : the larva is 

 covered with long hairs in every part of the body, and 

 merely spins a thin transparent web enclosing the chry- 

 salis. The fourth seems to be typically distinguished by 

 flying during the day. The larva is generally or- 

 namented with tufts of long silky hairs, of which there 

 are two more conspicuous than the others near the tail^ 

 two more near the head, and two towards the middle of 

 the body. It is very clear that this family represents the 

 j or clear- winged sphinxes of South America; 



