YOUNa OF THE CRAB. 



269 



next stage completes the progressive metamor- 

 phosis, and the form of the crab is in all respects 

 assumed ; the power of swimming is laid aside, 

 and the little crustacean, although scarcely yet 

 the eighth of an inch in size, relinquishes its 

 mode of life, and its habit of living near the 

 surface, for a very different state amidst the rocks 

 and seaweed at the bottom. 



Strange as these successive alterations of form 

 and habits are, they are not more so than those of 

 other creatures with which we are more familiar, 

 as, for example, the mutation of the caterpillar 

 into a butterfly. But the result appears very 

 different. The caterpillar advances from its con- 

 dition to one not only displaying more complexity 

 of structure, but habits of vastly increased ac- 

 tivity, with power to range through the bright 

 sunshine, amidst the perfume of many-coloured 

 flowers, and amidst those sounds of joy of which 

 its senses beyond doubt have a perception. But 

 how different is the result as regards the zoea ! 

 Although its organs and faculties are much more 

 perfect when it assumes its permanent condition, 

 the scene of its future existence presents no anal- 

 ogy with that to which the caterpillar is advanced. 

 The waves, bright with sunshine, are no longer 

 the scene of its activity; it sinks to the bottom, 

 and the perfect condition of its habits and organs 

 consigns it to a state of comparative darkness and 

 inactivity. 



In this, as in all such instances however, we be- 

 hold an evidence of the inexhaustible variety which 



