GASTEROPODA. 



129 



Lamimua, Gray (batillaria, Cantor). Cerith, zonale. PI. VIIL, fig. 23. 



Shell without varices, caual straight. Chusan. 



The fossil potamides decussatus, Brug., of the Paris basin, resembles this 

 section, and retains its spiral red bands. ^ 



NEKiNiEA, Defrance. ^ 



Ett/m., nereis, a sea-nymph, 



Ex., N. trachea. Pig. 79. 



Shell elongated, many-whiiied, nearly cylindrical; aperture 

 channelled in front ; interior with continuous ridges on the co- 

 lumella and whirls. 



Fossil, 150 sp. Inf. oolite— U. chalk. Brit., Prance, Ger- 

 many, Spain, and Portugal. They are most abundant, and attain 

 the largest size to the south ; and usually occm- in calcarious 

 strata, associated with shallow-water shells. (Sharpe.) 



Sub-genera. 1. Nerincea. Folds simple : 2 — 3 on the co 

 liunella ; 1 — 2 on the outer wall ; columella solid, or perforated. 

 Above 50 sp. 



2. Nerinella (Sharpe), columella solid ; folds simple ; co- 

 lumeUar, — 1 ; outer waU 1. 



3. Trochalia (Sharpe), columella perforated, with one fold ; 

 outer wall simple, or thickened, or with one fold ; folds simple. 



4. Etygmatis (Sharpe), columella soud or perforated, usually 

 with 3 folds ; outer wall with 1 — 3 folds, some of them com- 

 plicated in form. Fig. 79.* 



? Fastigiella, Reeve. 

 Tijipe., P. carinata, Reeve. 



Shell like tm-riteUa ; aperture with a short canal in front (Mus., Cuming, 

 and Brit. M.). 



Apokrhais, Aldrovandus. 



Efym., aporrhais (Aristotle) " spout -shell" from aporrheo, to flow away. 



Sgn., chenopus Philippi. 



Type, A. pes-pelecani. PL IV., fig. 7, and fig. 80. 



Shell with an elongated spire ; whirls numerous, tuberculated ; aperture 

 narrow, with a short canal in fi'out ; outer lip of the adult expanded and lobed 

 or digitated ; operc. pointed, lamellar. 



Animal with a short broad muzzle ; tentacles cylindrical, bearing the eyes 

 on prominences near their bases, outside ; foot short, angular in front ; 



* Fig. 79. Nerinsea trachea, Desl., partly ground down to sliew the form of the 

 interior. Bath oolite, Ranville. Communicated hy John Morris, Esq. 



G3, 



