SCALARIA. 93 



mark (Lilljeborg) to the Canary Isles (M^Andrew) in 

 the North Atlantic^ as well as throughout the Mediter- 

 ranean^ Adriatic^ and JEgean. The depths given by 

 different authors vary from 8-40 f. ; and Mr. M^An- 

 drew found this species alive on the shore at Vigo and 

 Gibraltar. 



Montagu says that the purple dye issues from a gland 

 behind the head : the great beauty of its colour was 

 first noticed by Plancus in Mediterranean specimens. 

 The shell is the " small stair-case '^ of Petiver^ " bastaard 

 wenteltrapje '' of the Dutch according to Klein, " barred 

 wreath " of Pennant, and ^^ false wentletrap^'' of Da Costa, 

 the " true wentletrap '' being S. scalaris or pretiosa. 

 Our shell barely exceeds 2 inches in length. 



It is the Turbo clathrus of the 10th and previous edi- 

 tions of the ' Sy sterna Naturae/ as well as of the ^ Fauna 

 Suecica ; ' but the species so named in the I2th edition of 

 the ^Systema^ is described as having the base encircled by 

 a spiral keel or ridge, and is consequently not the British 

 species. Da Costa called it Strombiformis clathratus, ap- 

 parently from a habit, in which he indulged with a most 

 inconvenient pertinacity, of substituting new names for 

 old; the latter specific name, not having been adopted 

 by any subsequent writer, must be considered obsolete. 

 Gmelin and Mohr evidently mistook the Turbo clathrus 

 of Linne for his T. clathratus j which is a Trophon. 



3. S. Trevelya'na"^, Leach. 



S. Trevelyana, (Leach, M.S.) Winch, on the Greology of Lindisfarn, Ann. 

 PM. new ser. iv. p. 434 ; ¥. & H, iii. p. 213, pi. Ixx. f. 7, 8, and (animal) 

 pi. FF. f. 1-3. 



Body yellowish -grey or pale-fawncolour, with a faint tinge 

 of purple, minutely streaked and speckled with white : snout 



* Named in honour of the discoverer, Miss Emma Ti-evelyan. 



