TRICHOTROPIS. 247 



flexuous laminae, and irregularly striated ; nucleus small, 

 seldom if ever retained, in consequence of the terminal portion 

 being easily broken off. L. 0-6. B. 0-325. 



Yar. acuminata. Spire much longer and more tapering. 



Habitat : Hard ground, in the coralline and deep- 

 sea zones, on our northern coasts, from the Dogger 

 bank to the extremity of the Shetland Isles ; local, but 

 not rare. It is tolerably plentiful m the west of Scot- 

 land. North Channel, Irish Sea(Hyndman and J. G. J.) ; 

 Lough Strangford (Dickie); co. Galway (Barlee). The 

 variety is Zetlandic. Fossil on Moel Tryfaen, 1330- 

 1360 feet (Darbishire) ; Clyde beds (Crosskey) ; " Ire- 

 land, Bute, Richmond " (Smith) ; Cruden, Aberdeen- 

 shire, " from Crag beds n . ( Jamieson) ; Mammalian Crag 

 at Bridlington, and Coralline Crag (Wood) ; post-glacial 

 deposits in Norway, 0-80 feet (Sars) ; Uddevalla(J. G. J .); 

 Canada (Dawson) . Living in the Arctic Ocean of both 

 hemispheres, Sitka Island, Iceland, Faroe Isles, Norway, 

 United States, and Canada; depths recorded 5-150 f. 



In crawling it swaggers from side to side. The verge 

 is falciform, above the right-hand tentacle. Stimpson 

 says that the shell is frequently found in the stomachs 

 of haddocks in Casco Bay. Nothing can exceed the 

 beauty of the sculpture with which the shell is decorated ; 

 it is a piece of really dainty work. My largest specimen 

 measures seven lines in length, and belongs to the 

 variety. Sometimes either the spire or the mouth is 

 twisted on one side. North American specimens are 

 larger, thinner, and have more tumid whorls. 



The discoverer of this shell was Capt. Laskey, who 

 figured it in the 1st volume of the ' Memoirs of the 

 Werner ian Society ; ' he considered it the young of 

 Pennant' s Murex carinatus. For the same reason 

 which I gave for changing the specific name of Torellia, 



