MALACOZOA. GASTEROPODA. PULMOBRANCIIIATA. 97 



light brownish-yellow ; whorls three ; the spire very short ; 

 the mouth oblique, ovato-oblong, three-fourths of the whole 

 length, posteriorly acute, the outer lip thin. Length from 

 five-twelfths to half an inch. 



The animal has the body black, the foot oblong, with its 

 lower surface greyish- blue ; the shell until emptied appears 

 greenish-black; part of the last turn and the spire are fre- 

 quently whitish and opaque. 



Abundant by rills, as on the south bank of the Don be- 

 tween the bridges, and on the north side near the Cruives, 

 crawling on the rocks, straws, and leaves ; not in the water, 

 but generally bedewed with it ; also on plants by the Canal, 

 and in mill-dams. 



Succinea Pfeilferi. Gray's Turton, 179. — Siiccinea gracilis. 

 Alder. Mag. Zool. and Bot. ii. 106. — Succinea putris var. a. Jef- 

 freys. Linn. Trans, xvi. 325, 505. — Succinea Levantina. Des- 

 hayes, Lamk. Syst. Ed. 2. viii. 317. 



Genus 6. Bulimus. 



Animal with the body elongated, spiral, the head with 

 four tentacula, the upper long, the lower short, all ter- 

 minating in a knob ; the foot small, elongated. 



Shell ovate, oblong, or sub cylindrical, spirate, thin ; 

 the last or body-whorl proportionally larger than the 

 next ; aperture oval, entire, toothless, not half so long 

 as the spire ; peristome incomplete, thickened. 



When the animal is in motion, the shell is balanced 

 obHquely on its back, or dragged along the ground. In 

 dry weather, or at the approach of winter, it retires 

 within the shell, and closes its aperture with a thin 

 membrane. 



1. BuUmiis luhricus. Glossy Bulimus. 



Shell oblongo-cylindrical, shining, semitransparent, of six 

 moderately convex whorls, which are faintly striated trans- 

 versely, and distinctly separated by the well-marked suture ; 

 the apex blunt ; the mouth ovato-trigonal, with the peristome 

 thickened, but not reflexed, the columella covered by the thin 

 inner lip ; the colour olivaceous, the peristome whitish, or 

 pale purplish-red. Length three-fourths of an inch; breadth 

 less than half the length. 



The animal has the foot oblong, thick, obtuse behind, grey 

 beneath, dusky and granulated above ; the neck dusky, rugoso- 



