4S VOLVAKIA. 



forms for which Lamarck originally proposed the genus ; in all 

 the other recent species the lip becomes more or less thickened 

 with a slight varix. 



I figure the fossil form V. bidloides, Lam. (PL 3, fig. 28), 

 from the Middle Eocene of France and Belgium. 



M. PALLIDA, Linn. PI. 12, fig. 84. 



White or yellowish, sometimes obscurely banded in the centre. 



Length, G-'T inch. 



West Indie*. 

 M. LUCIDA, Marrat. PI. 12, fig. 85. 



White, lip slightl}' thickened ; spire obsolete. 



Length, '35 inch. 



Natal, So. Africa. 

 M. COMPRESSA, Reeve. PI. 12, fig. 86. 



Shining white, glassy, spire very short. Length, '4 inch. 



Habitat unknown. 



Dr. Weinkauff supposes this to be possibly a young shell of 

 M.-pallida, but the lip is too much thickened ; I am very doubtful 

 whether either this or M. lucida is distinct from M. lactea, 

 Kiener. 



M. MUSTELINA, Angas. PI. 12, fig. 87. 



Light brown, with two yellowish bands, bordered with darker 

 brown in series of spots. Length, 5 mill. 



Port Jackson; Botany Buy, Australia. 



This is possibly synonymous with M. obscura, Reeve a 

 s-pecies of which I have no specimens. There is some resemblance 

 in the coloring and form. 



M. FAUNA, Sowb. PI. 12, figs. 88-90. 



Pinkish or yellowish white, or pure white ; stouter than the 



preceding species. Length, -35-'45 inch. 



West Indies. 



With this may probably be united M. alabaster, Reeve (fig. 

 89 , and M. diaphana, Kiister, not Kiener (fig. 90). 



M. OLIVELL.EFORMIS, Jousseaume. PL 12, fig. 91. 



White, sutures canaliculate, columella four-plicate, lip toothed 



within. Length, - 4 mill. 



Habitat unkjiown. 



