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 mouth is shorter 
and less open, and it is less impressed on the columella 
above the folds. 
* Named after the distinguished British geologist, Mr Greenough. 
