70 



INTRODUCTION TO ZOOLOGY. 



The specific name, Anatifera^ or goose-bearing, by which 

 the most common kind of barnacle-shell (Lepas) is distin- 

 guished, commemorates this old traditionary error, which 

 is still current. On more than one occasion, when we 

 have been examining a sea-borne piece of timber, with its 

 crowd of suspended Barnacles, some casual spectator has 

 volunteered to point out to us the bill and feathers of the 

 future bird! 



We may smile at the extravagance of these ideas, and 

 wonder how fancy could have devised such tales. But the 

 wildest stretch of imagination could not venture upon anything 

 more wonderful than the real and simple facts respecting the 

 transformations of these animals. 



Before the shelly covering of 

 that Barnacle was secreted, the 

 creature, not fastened as now by 

 its fleshy pedicle, was free and 

 locomotive, with members well 

 adapted for swimming, and fur- 

 nished, like the fabled Cyclops, 

 with one central eye (Fig. 44). 

 The animal of that acorn-shell, 

 now fixed so immoveably upon 

 the rock, had, at one time, an 

 elliptic figure, two eyes mounted 

 upon footstalks, and six pair of 

 jointed legs, which, keeping 

 stroke like so many oars, pro- 

 pelled it onwards (Fig. 45). 

 At a certain period its erratic 

 habits were laid aside, its future 

 resting-place was selected, and then, attaching itself securely to 

 the place thus chosen, its shelly covering was secreted, and 



as the process went on, the 

 visual powers, no longer need- 

 ful for the welfare of the 

 animal, were extinguished 

 for ever. 



To Mr. J. Y. Thompson, 

 whose name we have already 

 had occasion to mention, we are indebted for the discovery of 

 these metamorphoses, which the researches of other observers 



Fig. 44. YOUNG OP LEPAS. 



Fig. 45. YOUNG OP BALANUS. 



