IANTHINA. 553 



T. pallida, Havvey. 



Subglobose, almost smooth ; circumference rounded, not an- 

 gulated. 



Plate LXIX. fig. 10, 11. 



Iantldna pallida, Harvey, MSS. cited by Thompson. — Brit. Marine Conch. 



p. 152. 

 ? I. nitem, Thompson (not Mcnke), Ann. Nat. Hist. vol. v. p. !)(>', pi. 2, f. 2. 

 Iantldna pat ula, Philippi, Moll. Sicil. vol. ii. p. 224, pi. 28, f. 14. 



This rare Ianthina is perhaps equally entitled to be 

 called patula, since both names appeared, as those of shells 

 positively pronounced distinct from any known species, 

 during the same year (1844) ; but as the shell had pre- 

 viously been well figured in the " Annals of Natural 

 History," as the /. pallida of Harvey's MSS., although 

 with " f nitens, Menke," prefixed (the caution was neces- 

 sary, as in the earlier works of that conchologist, the 

 descriptions were so brief as to render recognition most 

 uncertain), the balance seems in favour of the name 

 bestowed by the British writers. 



The shape of this elegant shell is globose-subtrigonal, 

 and the length and breadth are nearly equal. Its surface, 

 which is but moderately glossy, and nearly smooth, merely 

 presenting, in addition to its lines of increase, most deli- 

 cately fine but densely disposed and universally diffused 

 wavy spiral striulse, is of a very pale violet, but assumes a 

 deeper tone of colouring upon the columella, and towards 

 the extreme anterior extremity. There are three and a 

 half volutions, that, instead of continuously sloping from the 

 suture — which is but very slightly oblique, profound, and 

 even canaliculated eventually — are well rounded below, but 

 depressed above. The spire is extremely short, and, when 



VOL. II. 4 I! 



