22 



METHODS OF INSECT LIFE. 



was drawn out in orderly succession, until everything,, 

 horns included, was free, excepting the long leaping 

 legs, the hindermost of the three pairs. These were 

 left till the last, and seemed to need the utmost care 

 and management to get them safely out of their tightly 

 fitting covering ; but they came out all right, and the 

 real insect and its cast skin stood, as counterparts in. 

 almost all respects, side by side. 



:s^ 



Fig. 20. — 1 and 2, eggs; :-? and 4, pupae; 5 and 6, Potato Frog Fly: 

 nat. size and magnified. 



No general rule can, however, be laid down as to 

 distinguishing the stage of life of the " simihirly 

 changing " insects by absence of wings or wing-cases. 

 Aphides or Plant-lice have both winged and wingless 

 females ; in some of the Cockroaches the wings are 

 absent in the females ; so are they also in both males 

 and females of one genus of Earwigs.* Fig. 20 shows 

 a pujM, resembling the perfect insect, except in the 

 absence of developed wings and wing-cases. 



Without investigation as to internal condition or 

 development, the precise stage of advance of the insect 

 cannot be theoretically laid down, but without entering 

 here on points of internal organization (and excepting 

 Aphides, of which the development is a most intricate 

 study), the condition may be known, in a general way,. 

 as being that of larvfe whilst they are quite wingless,. 



• Chclidoura of Latreille. 



