264> FISSURELLID^. 



angular, usually less excentric than in the other species; it is 

 twisted a little to the left, and forms a spire of between one and 

 two whorls : slit rather narrower above than below, extending 

 (in adult specimens) from the middle of the front margin 

 between one-fourth and one-fifth of the way up, being closed 

 in the line of its previous passage, and becoming a rather 

 broad and shallow groove which is closely laminated trans- 

 versely : mouth varying in shape from oval to roundish-oval, 

 delicately scalloped and notched by the impression of the ribs : 

 inside porcelain-white and nacreous, exquisitely and closely 

 but irregularly lineated in a concentric direction ; the edges 

 of the slit and groove are thickened. L. 1.25. B. 1. 



Habitat : West coast of Scotland, and Shetland, in 

 20-75 f. (J. G. J., Barlee, and others); " at Oban it is 

 found alive under loose stones, which are uncovered at the 

 fall of high spring-tides, as well as by dredging ; the tide 

 sometimes retreats fourteen feet ^' (Bedford); co. Antrim, 

 off the Copeland Isles, in 20-60 f. (Hyndman) ; Dublin 

 coast (Thompson) . Red and Coralline Crag (Wood) ; 

 Opslo, near Christiania (Lyell); Belgian tertiaries (Nyst); 

 Lamato, in Calabria (Philippi). The correctness of this 

 last locality in some measure depends on the probabi- 

 lity of E. crassa being identical with E. decussata of 

 Philippi. Its foreign distribution, as a recent species, 

 is entirely Scandinavian. Loven, Malm, M'^ Andrew 

 and Barrett, Asbjornsen, and Koren have dredged it at 

 different points between Bohuslan and Drontheim, in 

 from 10 to 60 f. 



This noble shell is never likely to become common in 

 collections, until some plan is discovered for dredging 

 in rocky ground. The young differs from E. fissura 

 of the same size in being more depressed, and in its 

 peculiar sculpture. In that species the ribs are strong, 

 and the surface is coarsely cancellated ; in this the ribs 

 are fine and more numerous, and the surface is delicately 

 granulated. The rows of small white dots are always 



