52 NATICA. 



N. UMBILICATA, Quoj'. PI. 22, fig. 26. 



Shell thin, inflated, largely, obliqneh^ excavatel}- nmbilicated, 

 obscurely decussateh^ striated ; subtransparent white with zigzag 

 longitudinal light chestnut markings, often interrupted to make 

 spiral series. Length, -^^ inch. 



So. Australia. 



N. glohosa, Ten ison- Woods is a synonym. 



N. MACROTREMA, Ad. and Reeve. PL 22, fig. 27. 



Smooth, thin, very largel}' excavately nmbilicated; greenish 

 white. Length, 1 inch. 



Borneo. 

 Perhaps a faded condition of the preceding species. 



Subgenus Ampullina, Lam., Defrance, 1821. 

 N. FLUCTUATA, Sowl). PI. 22, fig, 28. 



Obliquel}' globose, rather thin, polished ; light fawn-color, 

 obscurely darker banded, overlaid with zigzag white streaks; 

 columella white, densely callous, bordered with chestnut, com- 

 pletely overlaj'ing the umbilicus; interior whitish, interruptedly 

 banded with light chestnut. Length, 2-2-5 inches. 



Philippines. 



It is N. imperforata, Jay. 



Subgenus Amaura, Moller, 1842. 



N. CANDIDA, Moller. PI. 22, fig. 29. 



Thin, imperforate, bulimiform, with considerably elevated 

 spire ; white, under a thin epidermis. Length, 12 mill. 



Greenland. 



Section Acrybia, H. & A. Adams, 1853. 

 N. FLAVA, Gould. PI. 22, fig. 30. 



Shell thin, subglobose ; aperture large, columella sinuous, a 

 little dilated above, umbilicus none ; white, under a thin straw- 

 colored epidermis. Length, 1 inch. 



Maine, Newfoundland, northwards ; 



Finmark, Nova Zembla. 

 N, aperta, Loven, and N. Smithii, Brown, are identical. 



