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INTRODUCTION 



TO THE 



MONOGRAPHS OF THE GENERA 



CYMBA, MELO, AND VOLUTA, 



By W. J. Broderip, Esq., F.R.S. and L.S., tfc, V.P.G.S. 



The genus Yoluta of Linnaeus contains forty-five species, and consists of testaceous Mol- 

 lusca, varying essentially in their form, their habits, and their geographical distribution. Some 

 are marine ; others are the inhabitants of marshes and the banks of rivers ; some have opercula. 

 others have none. The shells of some are covered with an epidermis ; others are without that 

 covering. Some breathe air, and would perish in water; others breathe only through the 

 medium of water. Some are carnivorous; others feed on plants. The base of the shells in 

 some is entire, in others it is notched ; in short, plaits on the pillar of the shell form the leading 

 distinction of a Linnean Voluta,* and the species recorded in the Systema Naturae are widely 

 diffused in regard to climate, both in the Old and the New World., 



The genus is divided by Linnaeus into five sections. The first consists of Mollusca with 

 Shells, the aperture of which is entire; and of this section Voluta Auris Midae, Linn., (Auricula 

 Midae, Lam.) and Voluta Solidula, Linn., (Tornatella solidula, Lam.) may be taken as 

 examples. 



The next section consists of the " Cylindroideae," and of this, Voluta porphyria, Linn., 

 (Oliva porphyria, Lam.) may be taken as an example : indeed, this section, which contains but 

 three species, consists entirely of the genus Oliva, Lam. Then come the " Ovatae," consisting 

 of the genera Marginella, Columbella, Cancellaria, Volvaria, and a small part of the genus Mitra, 

 Lam. We are next presented with the " Fusiformes," consisting of the genera Mitra. Turbi- 

 nella, and a part of Voluta, Lam.; and 



The last section, the " Ventricosae," is composed of another part of the genus Voluta, Lam., 

 (Les Gondolieres) which portion has been divided by the author of this Monograph, and affords 

 many of the species of the genera Cymba and Melo.f 



This statement refers to the genus Voluta as left by Linnaeus in the last edition of the 

 Systema Naturae ;£ but, in Gmelin's edition§ the number of species is increased to one hundred 



* Volutae genus facillime distinguitur columella plicata. Syst. Nat. p. 1195, ed. 12. 



t See Sowerby's Genera of Recent and Fossil Shells, No. 28, t The 12th « § The 13th - 



