MARSHAi.i. : AnnrrioNS to British conchoi.ooy. 209 



Hebrides, iSsf. ('Porcupine'); off the Fastnet, 57f. (Tattersall) ; 

 North Sea, "j^f., Great Fisher Bank, and S. and S.E. Shetlands, pro- 

 cured from trawlers (Simpson) ! S. Ireland, a trawled specimen, and 

 E. Orkneys, another trawled specimen (J.T.M.) ; Shetland-Faroe 

 Channel, 64of. ('Triton'). The records given in the Linnean Society's 

 Journal as to K islandicus being dredged by the 'Triton' off Peter- 

 head were lapsus peniice of mine for F. gracilis. The operculum of F. 

 islandicus is obtusely triangular, dark horn-colour, large, solid, and 

 closely and coarsely wrinkled in the line of growth. F. islatidicus has 

 a broad as well as a narrow variety. Some from the Shetlands are 

 unusually slender, measuring 5-in. in length by i^in. only in the 

 widest part ; but rougher ground in the same seas yields a much more 

 robust form, some of my specimens thence being fully 6in. by 2in. 

 These forms will no doubt in time receive distinct varietal names. The 

 normal dimensions of the type ar^ 5m. by i|in., though a specimen 

 in Mr. F. W. Wotton's fine series of this handsome shell from the 

 Irish Channel is 5f in. in length, and is unique in having the epidermis 

 perfect throughout. Another specimen from the same seas, in the 

 collection of Mr. Bartlet Span of Tenby, is just short of 6in. in length, 

 but has lost the bulbous apex. In these large specimens the epider- 

 mis is usually more or less abraded. Mr. Bartlet Span found a 

 specimen in Tenby harbour some years ago, which had most probably 

 been cleaned out of a trawl-boat. 



The peculiar bulbous apex, which is supposed to be a s[)ecific 

 character of this species, is locally variable. Specimens from Green- 

 land, Finmark, and the Shetlands have the spire gradually tapering to 

 a blunt point, while those from S.W. Ireland, the Irish Channel, and 

 adjacent coasts have the prominent bulbous apex depicted in leffreys' 

 figure, which is much broader than the following whorls. The shell 

 is more attenuated than either Jeffreys' or Sowerby's figures, especially 

 the lower half, and has a much longer canal ; Sowerby's figure should 

 also have the suture oblique and the whorls less tumid. An actual 

 specimen placed over these figures will show how very much they 

 are drawn out of scale. Sars gives an excellent figure of the northern 

 form {minus the bulbous apex) where, as in our seas, it is less rare 

 than it used to be. Dr. Morcli many years ago brought about twenty 

 specimens from Greenland when on a visit to England, and these sold 

 at from twenty to sixty shillings each. 



{To be continued). 



I Zoology, 1S83, vol. 17, pp. 95, 96, 97. 



