40 



INSECT LIFE. 



But many insects will not lay in confinement. They 

 are more apt to lay in confinement if caged with a 

 growing food plant of the larva. 



5. Caterpillars and the corresponding stage of 

 other insects with a complete metamorphosis are called 

 larvce. The singular form of this word is larva. 



6. When a larva is full grown it molts its skin 

 and appears in a very different form. This third 

 stage (the ^^^ being the first and the larva the sec- 

 ond) is called ih^ pupa. The plural of pupa is pupce. 

 In Fig. 18 there are represented two larvas on the 

 upper edge of a fragment of a leaf and a pupa sus- 

 pended from the lower edge. The pupae of butter- 

 flies are sometimes 

 called chrysalids.* 



7. Some larvae 

 before changing to 

 the pupa state spin 

 about the body a 

 silken case within 

 which the pupa 

 state is passed. Such 

 a case is called a 

 Sometimes a leaf is fastened about the cocoon 

 (Fig. 19) ; and some hairy caterpillars make their 

 cocoons largely of their own hair, fastening it to- 

 gether with a thin layer of silk. 



8. Following the pupa state is the adult or imago 

 state. 



Fig. 19.— a large cocoon within a rolled leaf. 



cocoon. 



* There are two forms of this word : first, chrysalid, with the plural 

 chrysalids ; and, second, chrysalis, with the plural chrysalides. The 

 singular form of the second and the plural form of the first are in more 

 common use. 



