rusus. 333 



triangularly oval, the base being the narrowest part, and 

 consist of an outer filmy sheath and an inner and thick 

 fibrous case ; the latter resembles in structure a cocoa- 

 nut husk ; the opening is a wide slit at the top. Mr. 

 Howse found six young in one capsule. The fry are 

 almost cylindrical and of a dark reddish-brown hue. 

 The shell goes by the name of " long neck ,} among the 

 Staithes fishermen. F. Turioni is distinguishable from 

 F. Norvegicus in having a longer spire, shallower suture, 

 compressed whorls, much stronger sculpture, a conical 

 apex, different colour, greater solidity, and especially in 

 the shape of the operculum. 



4. F. Islan'dicus"*, Chemnitz. 



F. Islandicus, Chemn. Conch. Cab. iv. p. 159, t, 141. f. 1312-3. 



Shell regularly spindle-shaped, in consequence of the elon- 

 gation of the base, not very solid for its size, nearly opaque, 

 slightly glossy : sculpture, numerous spiral ridges, which are 

 somewhat flattened on the body-whorl, but prominent on the 

 upper whorls and the base ; there are about 14 on the penul- 

 timate and each of the next four whorls, besides a few slight 

 intermediate striae ; they do not extend to the margin below 

 the suture ; the upper two whorls are smooth ; lines of growth 

 extremely fine and close-set : colour white beneath the epi- 

 dermis (Icelandic specimens have a pale flesh tint) : epidermis 

 cortical (like the bark of a birch-tree) , fa wncolour or yellowish - 

 brown : spire elongated and gradually tapering ; apex stiliform, 

 and exhibiting a prominent bulbous point, which is broader 

 than the first regidar whorl: whorls 9, convex, compressed 

 upwards ; the last is attenuated towards the base, and occupies 

 three-fifths of the shell : suture well denned and rather broad, 

 but not deep : mouth (exclusive of the canal) oval, not expand- 

 ing outwards as in the last two species ; length (including the 

 canal) rather more than two-fifths of the shell : caned very 

 long, more or less straight, semitubular, ending in a wide and 

 curved notch: outer lip nearly semicircular and somewhat 

 flexuous, slightly contracted above ; edge rather thin ; inside 



* Icelandic; 



