LEPIDOPTERA. 



219 



The larvae of the Flannel-moths are remarkable for the 

 possession of ten pairs of legs, 

 three thoracic and seven abdomi- 

 nal. All other known lepidopter- 

 ous larvae, except perhaps those 

 of Micropteryx, have lost some of 

 the abdominal legs. The cocoons 

 of these insects are also remark- FIG. 24 8.-Cocoon of . 

 able, being furnished with a trap-door (Fig. 248). 



Family PSYCHID^E (Psy'chi-dae). 



The Bag-worm Moths. 



The Bag-worms are those caterpillars that have the curi- 

 ous habit of building each for itself a silken sac covered 

 with little twigs within which it lives (Figs. 

 249 and 250). When the caterpillar wishes 

 to move from one place to another it pushes 

 forth the front end of its body and creeps 

 along, carrying its house with it. It is said 

 that the species that inhabit Ceylon are be- 

 lieved by the natives to be composed of 

 individuals who in a previous incarnation 

 were human beings and stole kindling-wood, 

 and who now atone for the theft by repeat- 

 ing the act as an insect. 



When a Bag-worm is fully grown, it 

 fastens its sac to a twig and changes to a 

 pupa within it. And here the females remain until death, 

 leaving their eggs within their 

 sacs. These females are grub- 

 like creatures without wings. 

 But the male pupa works his 

 way out from the lower end 

 of his sac and changes to a 

 winged moth. Figure 250 rep- 

 resents the sac of a male with the empty pupa-skin projecting 



FIG. 249. Bag of 

 Oiketicus abbotii. 



emales 



4 



FIG. 250. -Bag of 



FIG. 251 Psyt 

 confederatn. 



