CIKKHOI'ODA. 



on the lower part of the abdomen. These cirri, however, may be 

 considered as analogous to the articulated appendages of certain 

 ies of Teredo, while the ganglions in some respects are mere 

 re] K-titions of the posterior ganglion of the bivalves. The position 

 of these animals in the shell is such, that the mouth is at the bottom 

 and the cirri near the orifice. Between the last two cirri is a long 

 ll 'shy tube, that has sometimes, but erroneously, been takon for their 

 proboscis, and at the base of which, near the back, is the opening of 

 the amis. Internally, we observe a stomach inflated by a multitude 

 of small cavities in its parietes, which appear to fulfil the functions 

 of a liver, a simple intestine, a double ovary, and a double serpentine 

 oviduct, whose walls produce the prolific fluid, and which, prolonged 

 in the fleshy tube, open at its extremity. These animals are always 

 fixed. Linnaeus comprised them all in one genus LEPAS, which 

 Brugieres divided into two, that have in their turn been subdivided *. 



ANATIFA, Bru<r. 



A compressed m.mtle, open on one side and suspended to a fleshy 

 tube, varying greatly as to the number of testaceous pieces with 

 which it is furnished ; twelve pair of cirri, six on each side, those 

 nearest to the mouth being the thickest and shortest. The branchiae 

 are elongated pyramidal appendages, that adhere to the external base 

 of the whole of the cirri, or of part of them. 



The two principal valves, of the most numerous species (PENTA- 

 LASMIS, Leach,) resemble those of a Mytilus; two others seem to 

 complete a part of the edge of the Mytilus opposite to the summit, 

 and a fifth azygous one unites the posterior edge to that of the oppo- 

 site valve ; these five pieces cover the whole of the mantle. From 

 the usual place of the ligament arises the fleshy pedicle ; a strong 

 transverse muscle unites the two first valves near their summit; the 

 mouth of the animal is concealed behind it, and the posterior extre- 

 mity of its body, with all the little articulated feet, is a little beyond 

 it, between the four first valves. 



The most common species of the European seas, Lepas ana- 

 ra, L., owes its specific appellation to the fable which repre- 

 sents it as producing the Bernacles and Macreuscs, a story 

 founded mi the rude resemblance that has been observed to exist 

 Ix-uveen the pieces of this shell, and a bird. The Anatifae ad In re 

 to rocks, piles, keels of vessels, &c. f We may distinguish 

 from them 



I his name of Lepas formerly belonged to the Patella, Linnaeus, 

 that some of these Cirrhopoda cxi-tnl \\hidi had no shells, gave them the name of 

 Triton : hut th. i uons is not confirmed, and we are to conclude 



mi-nix au tiu .miiuiil of an Anatifa ton\ turn it- shell. 

 / ,..w ansertfeta, Chemn., VFII, r. s.,ti ; Anat. dentata, Brug.. 

 M th.'.l pi. 166, f. 6, or Ptntalasiuisfalcala, Leach, Edinb. Encyc. 



