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. Itisa 
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 1-20th, 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 aninch. 
The smaller figure is of the size of nature. 
