6 THE SEA-SIDE AND AQUAEIUM. 



covered with Acorn shells, but these, before making 

 the sketch, I removed, in order to give my readers a 

 better idea of both molluscs. 



COMMON LIMPET (P. Vulgata.), with Barnacles* attached. 



An extraordinary fact in connexion with the little 

 Barnacles remains to be mentioned. This is the 

 transformation they undergo. In describing it, we 

 may avail ourselves of the elegant account of Mr 

 Gosse : 



" It " (the Barnacle) " begins life in a form exactly 

 like that of a young Entomostraceous Crustacean (or 

 Water-flea), with a broad carapace, a single eye, two 

 pairs of antennae, three pairs of jointed, branched, 

 and well-bristled legs, and a forked tail. 



" It casts off its skin twice, undergoing, especially 

 at the second moult, a considerable change of figure ; 

 at the third moult it has assumed almost the form of 

 a Cypris, or Cy there, being enclosed in a bivalve 

 shell, in which the front of the head, with the anten- 

 nae, is greatly developed, equalling in bulk all the 



