42 



V. — On the Characters of the several Amj)Mlious Vokttes 

 allied to the genus Mekunjyus. By William Swainson, 

 Esq., F.E.S., dc. [Read %th April, 1854.] 



Between the Phytophagous Mollusae, which live either 

 upon land or in fresh water, and the marine division, which 

 subsists upon seaweeds, there seems to intervene a remarkable 

 group of animals of this class, which, although organized 

 to enjoy life in both elements, can do so only by alter- 

 nately changing one for the other. They are, in short, 

 amphibious molluscce, and have been placed in our arrange- 

 ment next to the Linnean genus Turlo, because several 

 of these latter have the same peculiarity of habit and mode 

 of general structure. This curious group is probably 

 represented by the old Valuta Auris Midce of Linnseus, now 

 forming the modern genus Geovula, or Melampus of Mont- 

 ford. In these as well as the subordinate forms of Tedipes, 

 by Adamson ; Bcarahus, Montf ; ^ndi Rhodostoma, Sw.; 

 the pillar, and often the outer lip, is marked by distinct 

 plaits or folds, perfectly analogous to the Volutida. Hence 

 they have been termed amphibious Volutes. 



It must be confessed, however, that our knowledge of 

 most of these animals, and even of their shells, is as ye 

 very imperfect. 



The opportunities enjoyed by Guilding and Lowe of exa- 

 mining the animal, and witnessing the habits of Melampus 

 and Pedipes, completely estabhshes the fact that they do not 

 belong to the Pulmonaria of Cuvier, and, consequently, have 

 nothing to do with the true land shells, or HelicidcB. Of the 

 other divisions I cannot find that any recent discoveries have 



