184 LECTURE XL 



The remaining genus of Multwalve shells is of 

 a more singular nature than any of the rest : it is 

 called Lepas or Barnacle : the shell consists of se- 

 veral unequal valves or pieces, and is affixed at the 

 base, in some species, to a long, wrinkled, leather- 

 like tube ; and in others immediately to the sub- 

 stance to which it is attached, without the inter- 

 vention of the leathery tube. The inhabiting animal 

 is of a very singular structure, and is a kind of 7V/- 

 ton, perfectly resembling the Linnaean genus Tri- 

 ton among the naked Mollusca : the body is oval, 

 of a soft consistence, furnished with a long tubular 

 trunk, surrounded by several pair of long, curved, 

 jointed arms or tentacula, which taken all together 

 have a kind of feather-shaped aspect. 



Among those species of Lepas in which the 

 shell is seated on a tubular process, one of the most 

 common is the Lepas ana t if em, or Barnacle Shell. 

 It is frequently found adhering to the bottoms of 

 ships, to rocks, and other marine substances, whe- 

 ther fixed or floating, and is sometimes seen single, 

 and sometimes in groupes : the leathery tube is 

 from one to two inches in length, and the shell it- 

 self somewhat more than an inch long : its colour 

 is white, slightly clouded with blueish brown, and 



