166 



INVEirn^WiATE ANUrALS. 



Motlis, and Beetles — pass through tliree stages, just as (hi the pre- 

 ceding, but tliese stages differ frum uiie auotlier very uuieh in 

 appearance, and the nietaniorjilioKis is tlierefure said to be " com- 

 plete " (tig. 11:2). In these in.sects the larva is worm-like, .segmented, 

 and usuall}' fiu'nished witli hicoUKitive feet, which do not correN|ioiid 

 with the three pairs proper to the adult (see figs. \i>H, 124), though 

 the.se are usual])' present as well. Sometimes feet are wanting alto- 

 gether. The larva is also ymivided with masticating oi'gans, and 

 eats viiraciously. In this stage of the metamoi'phosis, the larvfe 

 constitute what arc popularly known as '"caterpillars" or '' gruhs." 



Fi;.;. llJ.-Mrl.-niiovi,li,isi,s of l.liu M,VfV'":-m"<''>i (rh„hr„n ,i,vssnla ri<iltt). 



Having ]x>]uaincd in this cduditiim for a Icmgcr or .shoi'ter time, and 

 having undergone ic]ieated changes iif skin, necessitated by its rapid 

 growth, the larva )iasses inti. the seciind .stage, anil licc(imes a pupa 

 (Hg. l■2:i^M■l^ also lig. ] li'i. ]u this stage the insect remains (piies- 

 cent, iulIcss irritateil, and it is very (.ften attached tii some foreign 

 olijci-t, so as to lie (piite inca|i;i.l)lc of changing its place. In the case 

 of the Jluttc'rflics and Moths, the pupa, constitutes what is familiarly 

 known as the "chrysalis." The lioily is protected liy a chitinous 

 )«'llirle. .-lud in some cases this is still further protecteil liy the dried 

 skin of the- larva; whilst in (.tlicr cases the larva— immediately 



