MULTI VALVES LEPAS. 7 



tionable species in which a resemblance is difficult to be 

 traced; as, for example, in the Lepas Scalpellum, Anse- 

 rifera, Anatifera, and varieties emanating from them. 



These three species are closely allied to each other, but 

 exceedingly dissimilar to the rest of their genus, for the 

 generality of Lepades are affixed to other bodies or sub- 

 stances, by their own proper base, or lower part of their 

 shells; whereas, these are attached by a stalk, stem, or 

 pedicle, which proceeds from the base of the shell to the 

 substance which sustains it. 



This peculiar structure engenders the idea of comparing 

 them to the form of certain dwarf plants, as the crocus, 

 and others of the like description, to which, in appear- 

 ance, they bear considerable analogy. 



The stem which supports the shells often differs ex- 

 ceedingly in quality and substance ; sometimes it appears 

 like a smooth, film-like tube, of a texture finer and thin- 

 ner than gold-beater's skin, though somewhat lighter co- 

 lored, and not unfrequently tinted with bright red or 

 orange ; at others, it is of a dark or blueish-brown, much 

 coarser, and wrinkled or granulated, with little verrucee 

 or warts. 



The Lepas Anseriferaand Anatifera, are almost invari- 

 ably composed of five valves, and it is to these species 

 that they ascribe the origin of the Barnacle or Brent-geese, 

 and are, therefore, commonly known by the name of 

 Goose-shells or Duck-barnacles. The I^epas Anserifera 

 is sometimes found in a fossil state. 



The Indian, American, Atlantic, and Arctic Oceans, 

 alike provide a habitat for the species of this genus; and 

 no less than eleven of them are to be occasionally met 

 with on the British Coasts. 



The Lepas, in all probability, derives its name from its 



