GASTEROPODA. 55 
This shell may be considered to form only a section of Zittorina, agreeing in the 
general characters with the genus Pagodus of Gray, with which, probably, the discovery of 
more perfect specimens may assimilate it. 
AMBERLEYA (Pacopus) Noposa. Plate V, fig. 19. 
TEREBRA NoposA, Buckman. 1845. Geol. of Cheltenham, p. 102. 
A. Testé turritd, ventricosd; spird elatdé, apice acuto; anfractibus (6) infra nodulosis, 
nodulis numerosis superne apud suturam cingulo nodulorum minorum ornatis; anfractu 
ultimo basi costulis obscuris tribus cincto. 
Shell turreted, ventricose; spire elevated; apex acute; whorls (6) convex on their lower 
portions, and nodulated; the nodules closely arranged, and forming a small belt near to 
the base of the whorl; another, much smaller and indistinct, circle of nodules encompasses 
the whorls upon their upper portions near to the suture; the last whorl has at its base 
three indistinct, narrow, encircling coste. 
The number of nodules gradually increases in each volution, the last whorl having 
about 18; the last two volutions are very ventricose, which give to the spire a slightly 
concave figure; in the younger state, consequently, the figure is more slender than in the 
adult. Our two specimens, which are of different stages of growth, present the following 
proportions : — Adult. Axis 24 lines, transverse diameter 15 lines, length of aperture 11 
lines, breadth of aperture 8 lines. Young state. Axis 16 lines, transverse diameter 9 
lines, length of aperture 6 lines, breadth 43 lines. 
Locality. Vt is very rare, the planking of Minchinhampton Common has furnished five 
examples, and several imperfect casts have been obtained in the Stonesfield slate at another 
place in the same vicinity: these casts have enabled us to ascertain the absence of a central 
columella. 
Ods. The specimen submitted to the artist was rather imperfect at the base of the 
aperture, which, together with the position, give it the aspect of a regular notch at that 
part of the shell. 
Family—NERITIDE. 
Nerita, Linn. 1738. 
Shell semiglobose ; spire short, sometimes not produced, consisting of few volutions ; 
aperture large, semilunar; outer lip thick, inner lip thickened, usually flattened, and 
striated or dentated at its immer edge. 
The fossil species of Werita, from the Great Oolite, may be divided into the three 
following sections, as dependent on the character of the inner lip :— 
