6 GLIMPSES OF NATURE. 



eyes succeed the Cyclopean and earlier state of 

 things. 



In this condition, the young acorn exactly resembles 

 certain of the adult water-fleas ; and it is also to be 

 noted that in the course of their own development 

 the crab and lobster tribes exhibit stages which 

 parallel the condition of the acorn just described. 



Then the days of its youth come to an end. The 

 feelers grow large and strong ; and a cement is poured 

 out from them which fixes the hitherto free-swimming 

 body to rock or shell (fig. 3, A.) The eyes disappear, 

 and the double shell vanishes away, to become re- 

 placed by the conical limy structure you see before 

 you on the stone. 



Last of all, the legs are changed into the plumes 

 or glass-hand of the adult acorn, which, to use the 

 words of a great naturalist, is thus only a kind of 

 degenerate crab, fixed head downwards as we have 

 seen in its shell, and kicking food with its legs into 

 its mouth. Thus we learn that to know an animal in 

 reality we must understand its becoming as well as 

 its being. The sea-acorn's history, in this sense, is 

 a lesson which holds good and true of all other living 

 things. 



