22 land and fresh- water shells of n. a. [part il 

 Spurious Species of Otinid.^;. 



Fig. 23. Velutina zonata, Gould, whose figure I copy (Invert. 



p. 242), is referred to this family under the name of 

 Morvlliiu zonata, Gray (see Gen Rec. Moll. II, 645). It 

 is a deep-water shell, without doubt belonging to Velutina. 

 Pfeiifer describes it also among the Otinea, as Otina zonata 

 (Mon. Auric, p. 12). 



Family LIMN.EID.E. 



Lingual membrane armed with numerous, quadrate teetla, 

 arranged in transverse rows, the central minute, the laterals 



Fig. '2A. 

 Lingual dentition of Ancyhi^ newbemji. 



uncinated or simply denticulated. Head with a broad, short 

 muzzle, dilated at the end ; mouth with one or more jaws ; 

 tentacles contractile, flattened or subulate, with the eyes ses- 

 sile at their inner bases. Mantle margin variously modified ; 

 respiratory orifice at the right side. Foot flattened, lanceo- 

 late or ovate. Excretory orifices on the left side of the neck. 

 Sexes united ; male and female organs with separate orifices, 

 on the right or left side. 



Shell of a varied form, thin, horn-colored, usually with an 

 oblique fold on the columella, and with the outer lip simple 

 and acute. 



Animal fresh-water, living in the water, usually coming to 

 the surface to respire the free air. 



The Limyisei.dse are found in every quaiter of the globe; but 

 in North America most of the genera are represented, except- 

 ing Cliih'na, Camptoceras, Amph ipeplea, Latia, &g. They are 

 more plenty in species and individuals in the more temperate 

 portions of the continent. Especially among the innumerable 

 lakes of the British possessions do the large species flourish. 



