196 CONTRIBUTIONS 



The smaller figure is of the size of nature. 



Observations. A single specimen only of this minute 

 species came into my possession. It most strongly resem 

 bles the pharetra, herein described. It may be distinguished 

 by its diminutive size, its flattened sides, its ribs and base. 

 With a microscope of considerable power, it was not possi 

 ble to discover any pores, which, I strongly suspect, exist 

 between the ribs. In this specimen there is no style, and 

 it may be doubted if it ever exist in this species. 



T.pharetra. Plate 6. Fig. 210. 



Description. Turbinolia clavate, longitudinally ribbed ; 

 furrows with a double row of minute perforations ; ribs 

 twenty-four, six of which terminate at a point on the cen 

 tre of the base ; six others terminate between these, higher 

 up ; these twelve being enlarged at the base, the remain 

 ing twelve, alternating, terminate above these again ; star 

 round ; style rather elevated, with six radii. 



Diam. .1, Length .3, of an inch. 



The superior view shows the stella of the style. 



The segment is a magnified view. 



Observations. In its form, this species has an almost 

 perfect resemblance to the sulcata (Lamarck). It differs 

 in the arrangement of the ribs, and judging from the figure 

 of Goldfuss (pi. 15, fig. 3), I should suppose it to differ in 

 the style also. The minute pores which exist in our spe 

 cies do not appear to be in the sulcata ; at least they are 

 not noticed by Lamarck or Goldfuss. Brogniart s figure* 



* Desc. Geolog. des Environs do Paris, pi. 8, fig. 3. 



