18 LITTORINID^. 



of the spire, the first minute and somewhat prominent : sutin-e 

 deep : mouth roundish-oval, scarcely expanding outwards : 

 outer lip thin, not much incurved above : inner lip reflected 

 on the pillar and at the base, behind which is a slight depression 

 or chink : operculum filmy, with a short spire, and dehcately 

 striated. L. 0-1. B. 0-065. 



Var. diversa. Longitudinal ribs finer and more prominent, — 

 a character which gives this variety a different aspect. 



Habitat : Widely distributed, in the lower part of the 

 laminarian zone and throughout the coralline zone, from 

 Guernsey to Unst, at a depth of fi'om 1-95 f. The 

 variety is fi'om Skye and Shetland. R. pundura occurs 

 in upper tertiary deposits in Sussex (Godwin- Austen) , 

 Ayi'shire (Landsborough, fide Thompson) , and at Udde- 

 valla (Malm), and in the post-glacial beds of Norway 

 at various heights from the present level of the sea to 

 100 feet above it (Sars) . Wood includes it (although 

 with a doubt as to the identity of the species) in his 

 ^Crag Mollusca,^ from the Coralline formation at Sutton; 

 but his description shows that the outer lip is notched 

 within, a character which the recent shell does not pos- 

 sess. It inhabits Bohuslan, according to Loven, who 

 called it R. textilis of Philippi ; Malm dredged it in the 

 same district in 10-60 f., Danielssen at Christiansund 

 in 40-60 f , M^ Andrew in Nordland, and Sars at Tromso, 

 Oxfjord, and elsewhere in Norway in 10-50 f. ; Tasle 

 found it in Brittany ; Martin has taken it in the Gulf 

 of Lyons, Mace at Antibes, Verany at Nice, Brusina in 

 Dalmatia, and M^Andrew off Orotava, Canary Isles. 



Of this species, again, we have two sizes, a large and 

 small one. 



It appears to be the Turbo retiformis of Montagu (from 

 Walker's doubtful description ?,nd.fi^\\XQ) , R. puncturata 

 of Macgillivray, R. appro xima of Brown, and Turritella 

 Dorvilleana of Leach. 



