20 METHODS OF INSECT LIFE. 



the Butterfly or Moth forms and matures till its time 

 for active life is come. Then it cracks the thin coat 

 and steps out, the moist wings soon spread, and in a 

 short time the insect occupies five or six times the 

 space it did before, and is perfect. 



The Beetle grub throws off its old skin, and lies as 

 a pupa (or chrysalis) in galleries in the timber where 

 the grub fed, or in the ground, or wherever its instinct 

 may have taken it, inactive, but in appearance much 

 like the Beetle, to which it will presently turn. Only 

 till complete in all powers, it lies with its limbs, 

 usually in separate sheaths, beneath it. (See Fig. 17, 

 preceding page.) 



The maggot of the Wasp, the Sawfly, the Gallfly, 

 and others of the Wasp order, also change (as we may 

 see in a piece of Wasp-comb) by 

 turning to pupae, in shape like 

 the perfect insect ; often in the 

 comb-cell where the maggot fed ; 

 often in a cocoon in the ground. 

 Fig. ib.-Larva and ^^ with some Sawflies and Ants ; 

 pupa of Marble-gall Fly. or in the Gall, which served 

 the grub at once for food and 

 shelter, as with many of the Oak and other Gall 

 Flies. 



The Dipterous maggot, that is the maggot of the 

 two-winged Fly, usually, or at least often, changes to 

 the pupa state within the oval case formed by its own 

 hardened and contracted skin. Sometimes the change 

 takes place in an outer film, showing the shape of the 

 liml)S within. See references, in list of Figures, to 

 Tipula and Triehoeera. 



These different methods of change show the kind 

 of transformations which the dissimilarli/ changing 

 insects go through ; that is, the insects which we 

 know as grubs, maggots, or caterpillars, in their first 

 stages. They leave oft" eating ; many of the cater- 

 pillars leave the place where they were feeding, and 

 being no longer observable on the plants, and the 



