MARINE MOLLUSCA OF THE UNITED STATES. 53 



Shell smooth, bright ; spire short or cancelled ; aperture truncated in front ; 

 columella plaited ; outer lip of adult with thickened margin. 



MARGINELLA, Lamarck. 



Genus VOLUTA, Linnaeus. 

 Syst. Nat., edit. x. 729. 1758. 

 1. V. JUNONIA, Chemnitz. Fig. 87. 



Conch. Cab., xi. t. 177, f. 1703, 4. 1799. 



Shell fusiformly ovate, spire short, obtuse at the apex ; whorls 

 smooth or minutely decussately striated, rather swollen around the 

 upper part; columella strongly four-plaited; aperture rather 

 long ; lip simple ; cream color, regularly painted with rows of deep 



red spots. 



Georgia, Florida. 



This is the most rare and valuable American marine shell ; spe- 

 cimens in good condition sell for fifty to one hundred dollars. Its 

 occurrence has been noticed at a number of localities, but it is 

 never plentiful. 



Genus MITBA, Humphreys. 



Mus. Gallon. 1797. 

 1. M. GRANULOSA, Lamarck. Fig. 88. 



Anim. s. Vert., vii. 304. 1822. 



Shell oblong, ovate, spire acuminately turreted, sutures rather 

 deep ; whorls closely decussated with granular ridges ; columella 

 four-plaited, slightly umbilicated ; aperture rather short. 



North Carolina, W. Indies. 



Genus MARGINELLA, Lamarck. 

 Prodr. 1799. 



1. M. GUTTATA, Dillwyn. Fig. 89, a, b. 



(Voluta.) Desc. Cat. 526. 1817 

 Marginella longivaricosa, Lamarck, Anim. s. Vert., vii. 358. 1822. 



Shell somewhat pyriformly oblong, flesh-colored, obscurely two- 

 banded, flaked throughout with opaque white spots ; spire small, 

 scarcely exserted, callous ; whorls rather gibbous around the upper 

 part ; lip broadly thickened, white, distantly spotted with reddish- 

 fawn. 



North Carolina to West Indies. 



2. M. ROSOIDA, Redfield. Fig. 90. 



Proc. Acad. Nat. Sciences Philad., 174. 1860. 

 Marginella apicina of American authors (not Menke). 



Shell rhombic-ovate, polished, grayish-brown, minutely flecked 



