50 lANTHINA. 



Species. 



1. FRAGiLis, f. 1-4, LaTYiarck. — Testa superne alba, sub- 

 angusta, infra planulata, ad angulum acute angulata ; 

 columella tortua, infra subacuta. — The only lantbiuse in 

 the Linnajan collection (Helix lanthina, Linn.) referred to 

 by Lamarck for this species are certainly specimens of this 

 sub-conical form, and agree with the figures cited from the 

 same author from Chemnitz. It is more sharply angular 

 than any other species, with the exception of Eeeve's 

 I. trochoidea. Reeve's /. affinis, I. roseola., and I. fibula 

 cannot be distinguished from this, and /. involuta is only a 

 partly unrolled distortion of the same species. 



2. TiiocHOiDEA, f. 15, Reeve. — Testa conica spira elevata. 

 — This shell, otherwise resembling the preceding, has a much 

 more elevated, conical spire. 



3. COMMUNIS, f. 7, 8, Lamarck. — Testa trapezoidea, quam 

 /. fragilis ad angulum magis obtusa, colore magis suffusa, 

 columella infra subacuta, anfractibus superne subplanulatis 

 declivibus. — Less angular than /. fragilis, but more so than 

 succeeding species. The upper part of the whorls is rather 

 flattened. /. Africana, Reeve, is a larger shell, but not 

 distinguishable from the above by any essential characters. 



4. Britannica, f. 5, 6, 14, Leach. — Testa subglobosa soli- 

 diuscula, purpureo intense suffusa, medio rotundata, vix angu- 

 lata, apertura flexuosa, sinu marginali obtusa ; anfractibus 

 superne subinflatis.— This species has been taken on the 

 coast of Cornwall after storms on English and Irish coasts ; 

 and what appears to be its young on the sands of Glamorgan- 

 shire, South Wales (the latter named /. Smithice, Reeve). 

 I can have little doubt in also associating /. grandis of 

 Reeve with this species. 



5. PLANOSPiEATA, f. 9-13, Ad. and Rve. — Testa sublen- 

 ticularis, anfractibus latis, medio rotundis, vix angulatis, 

 superne convexiusculis, depressis. — Of a depressed-convex or 

 lenticular form, more rounded than angular at the circum- 

 ference, and having the aperture wider than broad. It seems 

 impossible to distinguish from this species Reeve's L casta,, 

 I. depressa, and /. ca>ruleata. I. halteata is pro])ably the 

 young of the same. 



