History of British animals - University of Guam Marine Laboratory

312 MOLLUSC A. PECTIN IBRANCHI A. Scalaria.most prominent. Ribs distant, circular. Length an inch and a half, breadthabout half an inch.— Sower. Min. Conch, t. xvi. two upper figures In Crag,from Bramerton.2. S. semicostala.— AVhorls about 1, contiguous; spire transversely striated,ribs numerous, but slightly raised, lower part of each volution smooth, naked.— Sower. Min. Conch, t. xvi. middle figure.— In London Clay, from BartonCliff, and in Crag of Suffolk, (lb. t. 390.')3. S. acuta.— Whorls about 1, rather distant ;spire with three slight trans,verse risings, and a fourth very prominent one, near the lower part of eachturn, llibbs recurved, expanded, and acutely angular at their upper ends ;outer lip produced retrally.— Sower. Min. Conch, t. xvi. lowest figure.— InLondon Clay, Barton Cliff.4. S. snbulata.— Whorls contiguous; ribs 10 or 12, thick, 1— reflected; the interveningspaces smooth—Sower. Min. Conch, t. cccxc. f.Crag, Suffolk.5. S.foliacea.— Whorls separate ; ribs distant, slender, broad, leaf-like, reflectedin the middle.— Sower. Min. Conch, t. cccxc. f. 2.— Crag, Suffolk.6. S. minuta.— Whorls contiguous: ribs about 20, thin, obtuse, elevated.—Soiver. Min. Conch, t. cccxc. f. 3, 4.— Crag, Suffolk.Gen. LIII. CYCLOSTREMA — Spire short; transverseridges on the body-whorl disjoined from the pillar by acrenulated groove.262. C. Zetlandica.— Shell conical ; whorls 5, ribbed spirallyand transversely, with angular tubercles at the points of decussation.Mont. Linn. Trans, xi. 194. t. xiii. f. 3,— Zetland.Length 2 lines ; white ; apex obtuse; whorls tumid; longitudinal ridgesdo not extend to the lower part of the body-whorl, where the spiral ridgesare very prominent ; aperture nearly orbicular, and marginated. A singleexample of this species occurred to me among shell-sand at Noss, Zetland.It was lent to my valued correspondent the late Mr Montagu, who omittedto return it, so that I can add nothing to the description which he has published.Gen. LIV. DELPHINULA.— Spire depressed, produced,and tuberculated.263. D. calcar.— Whorls 4, the upper ones depressed, farminga flat summit.Mont. Test. Brit. Sup. 137, t. xxix. f. 3—On the shore of Iona, MrLaskey.Breadth about a quarter of an inch ;of a pale pink colour; round; on thebody and part of the second whorls are large, smooth, lanceolate spines, radiatingin straight lines from the shell, about 13 in number ; base convex,with a central cavity ; aperture orbicular.EXTINCT SPECIES.1. D. coronata Discoid beneath— flat above, with broad flat pointed spines aroundits edge concave Euomphalus ; coronatus, Soiver. Min. Conch, t.ccccl. f. 3.—Lower Oolite, AnclifK