422 Notes on the Classification of the Corliculadce, etc. 



I am led to make this remark, from the fact that Fischer, of 

 Paris, in his examination of the soft parts of Corbicula Largil- 

 lierti, discovered that this species has a syphonal retractory 

 muscle, rudimentary, it is true, but still quite evident, though 

 the shell (see Fig. 4) shows no indication of a broken palleal 

 line. So little is known of the anatomy of Corbiculadse, that I 

 think it not out of place to insert here a translation of Fischer's 

 paper, with the figures accompanying it. 



The Anatomy of Corbicula Largillierti, by M. P. Fischer. 



§ I. — Our knowledge of the anatomy of Corbicula is very 

 incomplete, no memoir of any extent having been published 

 on the subject. What we have is confined to a few words in- 

 serted by Rang in his observations on the animal of Gaiatea 

 radiata (Ann. Sc. Nat. t. XXV., 1832), and to the brief generic 

 characters given by Woodward, Gray, Adams, etc. 



Mr. Debeaux, during his residence in China, collected speci- 

 mens of the animal of Corbicula Largillierti, and entrusted 

 them to me. Although they have been somewhat influenced 

 by the strength of the spirits in which they were preserved, 

 they are still in such a state as to be able to afford us a correct 

 idea of the anatomy of Corbicula and of its zoological affinities. 



§ II. — The mantle. The animal is trigonal, much inflated 

 in the region of the beaks, and compressed towards the ventral 

 margin. The mantle, which is exceedingly thin and transpa- 

 rent, exhibits in certain places whitish spots, which are thick 

 and are encrusted with calcareous matter. I have already 

 noted a similar conformation in the mantle of Galatea. On 

 the anterior side, the lobes of the mantle are united and remain 

 so, until they reach the centre of the anterior side of the mus- 

 cle ; they are then free to the base of the syphons, where they 

 are united again by the agency of a small bundle of muscular 

 fibres. In the space comprised between this point and the 

 superior and posterior margins of the posterior adductor, the 



