TO GEOLOGY. 183 



O. Greenoughi* Plate 6. Fig. 197. 



Description. Shell fusiform, subulate ; substance of the 

 shell thick ; spire much elevated, pointed ; whorls six, 

 slightly impressed above the suture ; columella irregularly 

 folded at the base ; mouth rather wide, nearly one half the 

 length of the shell. 



Length 1.6, Breadth .5, of an inch. 



Observations. This species has the most elevated spire 

 of any Oliva I have seen. It has some resemblance to the 

 subulata (Lamarck), a recent species, but is a more slen- 

 der shell, and has a much more elevated spire. It is re- 

 markable for its spire and the shortness of the mouth. 



O. dubia. Plate 6. Fig. 198. 



Description. Shell ovately fusiform ; substance of the 

 shell thick ; spire elevated, pointed ; whorls five, slightly 

 impressed above the suture ; columella irregularly folded 

 at the base ; mouth wide, three fifths the length of the shell. 



Length 1.5, Breadth .6, of an inch. 



Observations. This species very closely resembles the 

 last described, but is less elongate. It has some resem- 

 blance to the plicaria (Lamarck), 'but the moutn is shorter 

 and less open, and it is less impressed on the columella 

 above the folds. 



* Named after the distinguished British geologist, Mr Greenough. 



