476 NEW GENUS OF MOLLUSKS. 



front, forming an elongated finger-shaped process, which 

 it employs as an exploring organ. The lateral lobes in like 

 manner may vary in their outline, tapering in front to 

 form on either side a salient angle which curves outwards, 

 or a portion of the thin margin, which partially overlaps 

 the shell, is produced into a rounded lobe or process ; the 

 two lateral lobes are continuous behind, and may extend 

 much more beyond the shell and posterior lobe than is 

 represented in M. Uang's figure. The Sulla smaragdina 

 of Lewkart, which is formed into a genus by Ehrenberg, 

 under the name of Cryptocephalus olivaceus (Symbols 

 physicae Mollusc Tab. 1, f. 4), is totally distinct from 

 Smaragdinella viridis. Smaragdinella is amphibious and 

 entirely marine, crawling slowly on rocks immediately 

 above the ripple of the sea. The animal of Smarag. 

 viridis is dark olive-green, speckled and mottled with a 

 yet darker shade ; the margins of the foot, those of the 

 lateral lobes, and of the head-disc are of a lighter green ; 

 and the eyes are black. 



