1462 THE STORY OF THE UNIVERSE 



undergo a process of metamorphosis essentially re- 

 sembling that of the butterfly; the characteristic fea- 

 ture of this form of development being that while the 

 caterpillar stage is passed in activity, the pupa or 

 chrysalis is quiescent; and from this resting-pupa the 

 active, winged insect comes forth. The dragon-flies, 

 crickets, grasshoppers, and their allies, undergo, on 

 the other hand, a less perfect series of changes than the 

 foregoing insects. The young grasshopper, on leav- 

 ing the egg, bears first a close resemblance to the 

 perfect insect. It is, further, not of worm-like con- 

 formation, and in these two points differs from the 

 larva of the other forms. Then, thirdly, it does not 

 inclose itself in a cocoon-case, but passes its chrysalis 

 stage in a free and active condition. In this respect it 

 again differs from the butterfly chrysalis; and its per- 

 fect form is attained simply by the development of 

 the wings. So that, in reality, the chief difference 

 between the young and the perfect form of the grass- 

 hopper consists in the non-development in the former 

 of the wings, which are thus characteristic of the 

 adult form. 



The dragon-flies illustrate an essentially similar 

 kind of metamorphosis, but also exemplify differ- 

 ences in the details of their development. The young 

 of the dragon-fly are active creatures, inhabiting the 

 water of pools; the eggs from which they are pro- 

 duced having been deposited by the parent in bunches 

 on the leaves of water-plants. The larvae are of 

 brownish color, and possess six legs, and a peculiar 

 apparatus of jaws, consisting of a pair of nippers 

 attached to a movable, rod-like stem. This appara- 



