456 MOLLUSCA SUB-KINGDOM VI 
Family 1. Hulimidae. Fischer. 
Small, polished, elongate-conic shells, with ovate apertures ; the axis often distorted ; 
nucleus dextral. Trias to Recent. 
Eulima, Risso (Fig. 861). Turreted, smooth, lustrous, 
without umbilicus. Trias to Recent. 
Niso, Risso (Fig. 862). Like the last, but with deep 
umbilicus reaching to the apex. Trias to Recent. 
Family 2. Pyramidellidae. Gray. 
Shell turreted to elongate-oval. Aperture oval, an- 
teriorly rounded, or with faint canal; outer lip sharp. 
Operculum horny, spiral. Marine. Cambrian to Recent. 
Fia. 861. 

pee 5 The nucleus consists of several whorls, and in 
nid, Ten. *Plio- Fic. 862. Palaeozoic and Mesozoic forms is coiled in the same 
cene; eariei sf goleraienens direction as the remainder of the shell. But in the 
polita, Linn. cene; Monte younger and more typical genera it is heterostrophic, 
Uae aa nario near distinctly separated from the rest of the shell, and often 
stands at an angle with the adult spire. It is question- 
able whether forms older than the Cenozoic can be retained in this family ; Fischer 
places most of them in a new family, entitled Pseudomelaniidae. 
Macrocheilus, Phil. (Macrochilina, Bayle ; Strobaeus, de Kon.), (Fig. 863). Elongate- 
oval, without umbilicus, smooth or with slightly curved growth- 
lines. Spire acuminate, only moderately high; last whorl 
large. Aperture angular posteriorly, sometimes 
with shallow anterior canal. Inner lip with 
weak anterior folds. Silurian to Trias. 
? Ptychostoma, Laube ; ? Undularia, Koken. 
Trias. 
Loxonema, Phil. Turreted, whorls arched, 
with S-shaped growth-lines. Sutures deep ; 
aperture higher than wide, with shallow canal. 
Silurian to Trias; particularly 
abundant in the Carboniferous. 
Zygopleura, Koken. Like 
the last, but whorls with sharp, 
slightly curved transverse ribs, 
or transverse nodose keel. De-  araoncheitus arculatus. 
vonian to Lower Cretaceous. Schloth. sp. Middle De- 
Bourgetia, Desh. (Pithodea, Golepae: eat 
de Kon.). Large, elongate-oval 
to turreted, with large, inflated body whorl. Surface 
marked with spiral striae or furrows. Carboniferous 

Fia. 863. 

Fia. 864. 
eaten and Upper Jura. 
Pseudomelania BEDI Pseudomelant Picte vi vee VOrl 
nia, Pictet (Chemnitzia, p.p. dOrb. 
Heddingtonensis, Pseudomelania geo OE ’ ( » Py} ); 
Sowb. sp. Ox: (Bayania) lactea, (Fig. 864). Turreted, with numerous, almost flat 
fordian ; France. lam. (sp (Cale aiveaa . yy ap. eee x ae 
Bands of original  caire Grossier ; whorls, and slightly impressed sutures. Surface 
eR oo ae on, aleer smooth, or marked by fine growth-lines ; aperture 
showing. aris. ° = ies . oa. 
’ i rounded anteriorly, or with faint canal. Umbilicus 
wanting ; rarely an umbilical fissure present. Very abundant in the Trias and Jura, 
less so in Cretaceous and Eocene ; probably present also in the Carboniferous. 
Sub-genera: Oonia, Microschiza, Gemm. ; Hypsipleura, Anoptychia, Koken. Trias and Jura. 
Coelostylina, Eustylus, Spirostylus, Kittl. Trias. Bayania, Munier-Chalm. Eocene. (Fig. 865.) 
