102 CONTRIBUTIONS 



The smaller figure is of the size of nature. 



Observations. This minute species resembles P. notata 

 above described, but has not the marks of growth. It is a 

 smaller species, and the whorls are not quite so flat. 



P. aciculata. Plate 4. Fig. 82. 



Description. Shell acicular, highly polished ; substance 

 of the shell thin ; apex very acute ; suture linear, very mi- 

 nute ; whorls nine, flattened ; mouth elongate, acutely an- 

 gular above obtusely angular below, about one fourth the 

 length of the shell ; columella slightly thickened ; outer 

 lip edged. 



Length 3-20ths, Breadth l-20th, of an inch. 



The smaller figure is of the size of nature. 



Observations. This is the most attenuate of the genus, 

 so far as my observations have extended, and is an interest- 

 ing minute species, remarkable for its high polish and 

 delicate form. 



P. striata. Plate 4. .Fig. 83. 



Description. Shell conical, transversely striate ; sub- 

 stance of the shell thin ; apex rather acute ; suture im- 

 pressed ; whorls eight, rounded ; mouth subovate, about one 

 fourth the length of the shell ; columela flattened at the 

 base. 



Length 4-20ths, Breadth nearly .1, of an inch. 



The smaller figure is of the size of nature. 



