SUB-ORDER D 



STY LO.MM. \TOPHORA 



Superfamily 3. AULACOPODA. Pilsbry. 



l<'<K>t with longitudinal grooves above and parallel with its lateral margins. 



Familv 1. Zonitidae. 



Aulacopoda with a spiral, conic, or helicoid shell, sometimes partially uncoiled, 

 usually smooth and with simple lip ; marginal teeth of the radula thorn-like ; foot 

 iintnihi wide; JOAV rather smooth. Carboniferous (?) to Recent. 



I'/'trina, Drap. Shell small, translucent, with short spire, and very large body 

 \vhorl. Tertiary and Recent. 



Archaeozonites, Saiulb. (Fig. 1045). Thick-shelled, globose, with rather high spire, 

 deeply umbilicate ; outer nun-gin sharp. Oligocene and Miocene. Here also should 



Ki<;. 1045. 



Archaeozonites subverticillus, 

 Saudi). Lower Miocene; 

 Eckingen, near Ulm. 



FIG. 1046. 



Hyalina denudatn, 

 Reu'ss sp. Miocene ; 

 Tuchoritz, Bohemia. 



Fir,. 1047. 



Lychnus Matheroni, Requien. 

 Upper Cretaceous (Garunmiai,) ; 

 Rognac, Provence. 



be placed, perhaps, the archaic Helix-sliaped snails from the Coal Measures of Nova 

 Scotia. 



Zonites, Montf. Like the last, but with thinner shell, granulated above, and 

 smooth below. Tertiary and Recent. 



Hyalina, Fer. (Fig. 1046) ; Omphalosagda, Sandb. ; Ariophanta, Desm. ; Trocho- 

 morpha, Albers. Tertiary and Recent. 



Lychnus, Montf. (Fig. 1047). Body whorl large, bent upward at first, and later 

 decurved, so that the margins of the aperture lie in the basal plane. Upper Cre- 

 taceous of Provence and Spain. 



Family 2. Limacidae. Lamarck. 



Naked slugs having a small vestigeal shell, flat and non-spiral, concealed within the 

 mantle, which latter forms a small oval shield on the forepart of the body. Foot margin 

 narrow ; dentition and jaw as in the Zonitidae. Tertiary and Recent. 



The principal genera are Lima.c, Linn., in which the intestine has four longi- 

 tudinal folds, and the back is keeled at the tail only ; and Amalia, Moq.-Tand., with 

 spiral gut and strongly keeled back. Their small scale-like shells have been found 

 in the Tertiary and Pleistocene ; present distribution nearly world-wide. 



Family 3. Bndodontidae. Pilsbry. 



Shell spiral and external, varying from cylindric to helicoid and planorboid, usually 

 rib- sculptured and with opaque colouring; lip thin, unexpanded. Jaw of separate or 

 united imbricating plates, or solid and striated; marginal teeth squarish; genitalia 

 without accessory organs. Carboniferous to Recent. 



VOL. I 2 K 



