IN DESCRIBING SHELLS. 37 



Subiilata is when it is long and slender, as in Murex Haustellum, 



Trihulus, and cornutus. 

 Recta is when it stands in a straight line, as in Murex bahy- 



lonius. 

 Flexuosa is when it is bent on one side, as in Murex Lotorinm 



and Pyrum. 

 Recurva or Rejlexa is when the tail is bent back, as in Buc- 



cinum cornutum, rufum, and tuberosum. 

 Adscendens is when the tail rises upwards supposing* the shell 



to be laid with the mouth downwards, as in Murex Pileare, 



reticularis, and Vertagus. 

 Erecta is when the tail is turned quite upright supposing 



the shell laid with the mouth downwards, as in Murex 



Anus. 



OF THE LIPS, LABIA. 



Explanatum is when the left lip is spread out on the last 



whorl, as in Buccinum gibbosulum and neriteum. 

 Striatum is when there are lines marked on the inside of the 



outer lip, as in Buccinum hcemastoma and midosum. 

 Edentula is when the lips are without teeth on the edge, as in 



Nerita fiuviatilis and lacustris. 

 Dentatum is when there are sharp points or projections on the 



edge of the outer lip, as in Strombus Fnsiis. 

 Muricatum is when there are sharp points on the edge of the 



lip, but not so large as Dentatum, as in Buccinum Vibex and 



Erinaceus. 



