196 PSEUDOLIVA. 



M. TESSELLATA, Lesson. 



This species has not been recognized, never having been figured. 

 It is said to come from New Zealand — doubtless a mistake. 



M. ciNGULATA, Lam. 



This belongs to the Turbinelloid genus Leucozonia. 



Genus PSETJDOLIVA, Swainson. 



The shell has some resemblance to Monoceros in its tooth on 

 the outer lip, and its operculum is purpuroid ; it also resembles 

 the Olivancillarim The animal is unknown. H. and A.Adams 

 described a subgenus Macron^ in which are included several 

 species from the west coast of America, but this group must be 

 eliminated, as the operculum has since been ascertained to be 

 unguiculate. P. Austrolis is now placed among the Ehurnse as 

 subgenus Zemh'a. The genus thus limited embraces a few 

 African species, but is found in the eocene of Europe and 

 America. 



P. PLUMBEA, Chemn. PI. 61. tig. 310. 



.Smooth and polished, with sometimes faintly impressed revolv- 

 ing lines. Yellowish or brownish ; white or yellowish within 



the aperture. Length, 1-25-1 -75 inch. 



? Africa. 



Very probably the two next succeeding species are only dif- 

 ferent stages of the young of P. phctnbea ; xmfortimately the 

 material accessible is not sufttcient to permit a definitive conclu- 

 sion upon this point. 



P. STRIATULA, A. Adanis. PI. (il, fig. 311. 



Yellowish, no callus on the inner lip ; evidently quite immature. 



Length, -55 inch. 



Afriea. 

 P. SEPJMANA, Rang. PI. (')1, (ig. 312. 



Dull gray, reddish within the aperture and on the columella. 



Length, -75 inch. 



FriiHu', Mund, Africi. 



P. ZEBRINA, A. Adams. Pi. 61, fig. 306. 



Yellowish, with zebra-like longitudinal streaks. 



Length, -85 inch. 



Africii . 



