SUB-ORDER D STYLOMMATOPHORA 497 
Superfamily 3. AULACOPODA. Pilsbry. 
’ Foot with longitudinal grooves above and parallel with its lateral margins. 
Family 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 
margin wide; jaw rather smooth. Carboniferous (?) to Recent. 
Vitrina, Drap. Shell small, translucent, with short spire, and very large body 
whorl. Tertiary and Recent. 
Archaeozonites, Sandb. (Fig. 1045). Thick-shelled, globose, with rather high spire, 
deeply umbilicate ; outer margin sharp. Oligocene and Miocene. Here also should 

Fic. 1045. Fic. 1046. Fic. 1047. 
Archaeozonites subverticillus, Hyalina denudata, Lychnus Matheroni, Requien. 
Sandb. Lower Miocene; Reuss sp. Miocene ; Upper Cretaceous (Garumnian) ; 
Eckingen, near Uln. Tuchoritz, Bohemia. Rognae, Provence. 
be placed, perhaps, the archaic Heliz-shaped 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, Fér. (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 Limav, 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. Endodontidae. Pilsbry. 
Shell spiral and external, varying from cylindric to helicoid and planorboid, usually 
rib-sculptured and with opaque colouring ; lip thin, wnexpanded. Jaw of separate or 
united wmbricating plates, or solid and striated ; marginal teeth squarish ; genitalia 
without accessory organs. Carboniferous to Recent. 
VOL. I 2K 
