28 
ORDER II. —TRACHELIPODA. 
THE shells of this Order are spirivalve, ensheathing. It is separated into Two Sections, 
viz. Phytiphaga and Zoophaga. 
SECTION I.—__TRACHELIPODA PEYTIPHAGA. 
Aperture of the shell entire; base without any ascending dorsal notch or canal. 
Tuts Section contains Ten Families, viz. Colimacea, Lymnzana, Melaniana, Peristomi- 
ana, Neritacea, Janthinea, Macrostomiana, Plicacea, Scalariana, and Turbinacea. 
COLIMACEA.—11 Genera. 
Shell spirivalve, with no other projecting parts on the exterior than the strie of gronth; the right mar- 
gin of the aperture is often recurved or reflected outwards. 
Hetrx.—Shell orbicular, convex, or conoidal; sometimes globular, the spire rather ele- 
vated: aperture entire, transverse, very oblique, contiguous to the axis of the 
shell; the margins disunited by the projection of the penultimate whorl. 
Plate XIV. Fig. 17, H. heemastoma. (Idem.—Linn.) 
CarocoLtLa.—Shell orbicular, more or less convex or conoidal above; the circumference 
or periphery angulated or keeled: aperture transverse, contiguous to the axis of 
the shell; the right margin or lip subangular, often toothed or plaited beneath. 
Plate XIV. Fig. 16. C. albilabris. (Helix carocolla.—Linn.) 
Awostoma.—Shell orbicular, the spire convex and obtuse: aperture round, toothed with- 
in, grinning or shewing the teeth, turned upwards to the side of the spire; the 
margin of the lip reflected. 
Plate XIV. Fig. 18, 18 (a). A. globulosa. [Mrs. Mawe’s Cabinet. ] 
Heticrva.—Shell subglobular, imperforate: aperture entire, demi-oval. Columella cal- 
lous, transverse, rather flat, margin acute, forming an angle at the lower base of 
the right lip: operculum corneous. 
Plate XV. Fig. 1. H. major. (Gray, in Zool. Jour. Vol. I. p. 251.] 
Pura.—Shell cylindrical, generally thick: aperture irregular, demi-oval, the lower part 
rounded and subangular; the margins nearly equal, reflected outwards, disunited 
at the upper part by an interposed columella lamina, always affixed. 
Plate XV. Fig. 2. P. mumia. 
Cuavustt1a.—Shell mostly fusiform, slender, the summit rather obtuse: aperture irregular, 
rounded-oval; the margins united throughout, free, reflected outwards. 
Plate XV. Fig. 3. C. torticollis. 
Butimus.—Shell oval, oblong, or turreted; aperture entire, longitudinal; the margins ve- 
ry unequal, disunited at the upper part. Columella straight, smooth, the base 
entire, not channelled. 
Plate XV. Fig. 4. B. citrinus. (Helix perversa, Variety b.—Linn.) [Mrs. Mawe’s Cabinet. ] 
