GASTEROPODA. 51 



A small, slender species, with closely-arranged costse, which are rather large, but not 

 much elevated; the sutures of the whorls are strongly marked ; it is rare, but has occurred 

 in more than one of the shelly beds. Axis 10 lines ; transverse diameter 2 lines. 



Locality. Minchinhampton Common. 



This species is named in compliment to our kind and liberal friend, N. T. Wetherell,- 

 Esq., E.G.S. 



Chemnitzia variabilis. Plate VIII, figs. 7, la, b. 



C. Testa turritd, subulatd ; anfractibus convexiusculis, transversim striatis, plus minus ve 

 crenulatis, longitudinaliter costatis, costis curvatis circa 12 inambitu; costis interdum inter- 

 rwptis nodulosis ; aperturd ellipticd obliqud ; columella marginatd. 



Shell turreted, subulate ; whorls rather convex, transversely striated, striae more or less 

 longitudinally costated, costae curved, about 12 in a volution; ribs sometimes obsolete, and 

 replaced by nodules ; aperture elliptical, oblique ; columella marginated. 



Specimens differ in the convexity of the whorls, those which are most convex have the 

 ribs shortest, or reduced merely to nodules placed upon the upper border of each whorl : in 

 all specimens the costae become obsolete before reaching the base of each whorl. Occa- 

 sionally upon the same specimen the ribs degenerate into nodules, only the smaller whorls 

 are then costated. This species was first mistaken for Melania undulata (Deslongchamps) ; 

 but in that shell the sides of the volutions are flat, the costae are more numerous, and 

 extend to the junction of the whorls, and have no curvature except in the last one ; 

 they are likewise less subulate than in our species. Axis 5 lines ; transverse diameter 

 1^ lines. 



Locality. It is abundant in all the shelly beds of the Great Oolite, near Minchin- 

 hampton. 



Chemnitzia phasianoides. Plate IX, fig. 5. 



C. Testa ovato-subcylindricd, spird elatd, apice obtuso ; anfractibus (5) planis, anfractu 

 ultimo subcylindrico, elongato ; aperturd obliqud; labro dilatato. 



Shell ovately-subcylindrical, spire elevated, apex obtuse, whorls (5) flattened, the last 

 whorl subcylindrical, elongated ; aperture oblique ; outer lip dilated. 



This species has a considerable resemblance to Euliiua vagans, but the spire is much 

 shorter, the whorls are fewer, and the apex is more obtuse ; the aperture is rather narrow, its 

 length being two fifths of the entire shell. 



Locality. The planking of Minchinhampton Common has furnished our specimens. 



