DEFRANCIA. 365 



the mouth with a small tubercle or tooth : pillar long and 

 flexuous. L. 1. B. 0-375. 



Habitat : Not uncommon in the coralline zone 

 on the coasts of Guernsey, Cornwall, Devon, Bristol 

 Channel, Ireland (west, south, and east), and the Clyde 

 district ; Anglesea (M ^Andrew) ; Coldingham Bay, 

 Berwickshire (Maclaurin); Dunbar (Laskey); Orkneys 

 (Forbes); Shetland (Barlee and J. G. J.). Italian ter- 

 tiaries (Philippi and Calcara). Its present known dis- 

 tribution is entirely southern as regards the British 

 Isles, and comprises the sea-board of the Atlantic from 

 Cherbourg to the Canary Isles, the Mediterranean, 

 Adriatic, and iEgean; depths recorded by Forbes and 

 M^Andrew 4-80 f. 



Like all its molluscan kindred, it prefers, when in 

 captivity, darkness to light. My largest British speci- 

 men is from Unst, my smallest from Guernsey ; some 

 from Corsica are very diminutive. The tubercle on the 

 upper part of the inner lip and the angulated point on 

 the outer lip at the commencement of the fissure are 

 especially noticed by Millet among the characters of his 

 genus Defrancia. 



It is not the Murex gracilis of Brocchi, nor that of 

 Scacchi. Donovan described our shell as M. emargi- 

 natus, Michaud as Pleurotoma Comarmondi, Bronn as 

 P. suturale, and Costa as P. Cyrilli ; Chiereghini called 

 it M. Poelarius. The young appears to be P.fallax 

 of Forbes, and is the Fusus Branscombi of Clark. 



D. sinuosa [Murex siniiosus, Mont.) is allied to the 

 present species ; it is a native of the west coast of Africa. 

 Bryer is reputed to have found it at Weymouth, Laskey 

 at Dunbar, De Gerville at Quineville in the north of 

 France, and Martin in Provence. 



