GASTEEOrODA. 317 



Shell thin, flexible, ^lobosely-cylinflrical, spire fnincater!, 

 whorls channeled ; aperture long, expanded and deeply sinuated 

 in front, outer margin disunited at the suture ; colHimella open, 

 exposing the whorls. 



Animal with a short and simple head-lobe, truncated in front 

 and eyeless ; lateral lobes nearly concealing the shell ; lingual 

 teeth hooked and serrulate, laterals about 40, narrow, claw- 

 shaped ; gizzard armed with horny teeth. 



Distribution, 7 species. Greenland, Britain, Mediterranean, 

 Zanzibar, India, New Zealand. 



A. hulluta is found amongst weed, in 1 — 15 fathoms water. 

 (Porbes.) 



Cylich:n-a, Loven. 



Type, C. cylindracea, PI. XIV., Pig. 10. 



Synonym, BuUina, Eisso. 



Shell strong, cylindrical, smooth or punctate-striate ; spire 

 minute or truncated ; aperture narrow, rounded in front ; 

 columella callous, with one plait. 



Animal short and broad, not investing the shell; head 

 flattened, truncated in front, with sub -centrally immersed eyes, 

 tentacular lobes more or less united ; foot oblong, posterior and 

 lateral lobes not much developed ; gizzard armed ; lingual teeth 

 squarish, recurved and serrated, with 1 large and 5 or 6 small 

 hooked laterals. 



Distribution, 40 species. United States, Greenland, Britain, 

 Eed Sea, Australia. 



Fossil, Tertiary — . Britain. 



? Kledstella, a. Adams. 



Shell thin, dotted, striated, columella smooth, spire obtuse. 

 Distribution, 1 species. Japan. 



Amphisphyra, Loven. 



Type, A. pellucida, Johnst. [Amphisphyra, double hammer) 



Synonyms, Utriculus (part). Brown. Ehizorus, Montfort. 

 Diaphana, Brown. 



Shell small, thin, ovate, truncated, spire minute papillary, 

 aperture long. 



Animal entirely retractile into its shell ; head wide, short, 

 with lateral triangular tentacles ; the eyes behind them minute, 

 immersed ; muzzle bilobed in front ; foot oblong, truncated in 

 front, notched behind ; teeth 1.1.1, central quadrate, serrulate; 

 laterals broad, hooked. 



