The Imago. 65 



imago is accomplished. Sometimes the pupa is surrounded by 

 a silken cocoon, either thick, as the' cocoon of some moths, or 

 thin, as the cocoon of bees. These cocoons are spun by the 

 larvae as their last toil before assuming the restful pupa 

 state. The length of time in the pupa-stage varies from 

 a few days to as many months. Sometimes insects which 

 are two-brooded remain as pupse but a few days in summer, 

 while in winter they are months passing the quiescent period. 

 Our cabbage-butterfly illustrates this peculiarity. Others, like 

 the Hessian-fly and codling-moth, remain through the long, 

 cold months as larvse. How wonderful is this! The first 

 brood of larvse change to pupse at once, the last brood, though 

 the weather be just as hot, wait over inside the cocoon till the 

 warm days of coming spring. • 



THE IMAGO STAGE. 



This term refers to the last or winged form, and was given 

 by Linnseus because the image of the insect is now real and 

 not masked as when in the larva state. Now the insect has its 

 full-formed legs and wings, its compound eyes, complex 

 mouth-parts, and the fully developed sex-organs. In fact, the 

 whole purpose of the insect now seems to be to reproduce 

 itself. Many insects do not even eat,' only flit in merry 

 marriage mood for a brief space, when, the male flees this life 

 to be quickly followed by the female, she only waiting to place 

 her eggs where the prospective infants may find suitable food. 

 Some insects not, only place their eggs, but feed and care for 

 their young, as do ants, wasps and bees. Again, as in case of 

 some species of ants and bees, abortive females perform all, or 

 most, of the labor in caring for the young. The life of the 

 imago also varies much as to duration. Some live but for a 

 day, others make merry for several days, while a few species 

 live for months. Very few images survive the whole year. 



INCOMPLETE TRANSFORMATION. 



Some insects, like the bugs, lice, grasshoppers, and locusts, 

 are quite alike at all stages of growth, after leaving the egg. 

 The only apparent difierence is the smaller size and the 

 absence or mcomplete development of the wings in the larvse 

 and pupse. The habits- and structure from first to last -seem to 

 be much the same. Here, as before, the full development of 

 the sex-organs occurs only in the imago. 

 5 



