98 PYRAMIDELLIDif:. 



occurs in the glacial or post-glacial beds of Aberdeen- 

 sbire (Jamieson), at Bridlington (Forbes), as well as in 

 the Norwich and Red Crag. The shell has remarkably 

 strong and conspicuous spiral striae between the ridges, 

 and its base is encircled by a keel. 



I have a specimen of S. pseudoscalaris, Brocchi, which 

 the late Miss Lavars of Penzance picked up in Porth- 

 curnow cove near the Land^s End, together with S. 

 Turtonce, S. communis, and S. clathratula. Its nearest 

 ally is >S^. cominunis, from which it may be known by the 

 more conical shape, sharper ridges, and basal keel or 

 ridge. This species may be British ; for Tasle has re- 

 corded it from IVIorbihan, and Aucapitaine and Fisher 

 from the Charente-Inferieure. 



Acirsa borealis of Beck has been dredged in 18-20 f. 

 off the coast of Antrim by Mr. Hyndman, Mr. Waller, 

 and myself, and on the Aberdeenshire coast, from 3 to 

 8 miles from land, in 30-45 f., by Mr. Dawson. This 

 species has not been found li\dng south of Iceland. It 

 is the S. Eschrichti of Holboll (fide Moller), and Tur- 

 ritella Hibernica of Waller. Morch^s genus Acirsa seems 

 to connect the present family with the next. 



Family XYI. PYRAMIDEL'LIDJE, Gray. 



Body spirally twisted : head furnished with a long cylin- 

 drical and retractile proboscis; flap ("mentum" of Loven) 

 extensile, but rarely projecting beyond the foot: tentacles 

 conical or triangular, flattened, and smooth, with more or less 

 inflated tips : eyes sessile at the inner base of the tentacles, 

 and placed near to each other : foot lanceolate, and double- 

 edged in front. Branchial apparatus consisting of a single 

 gill-plume. Tongue unarmed or toothless. 



