T. testâ rotundato-cordatâ, gibbâ, sub-fuscâ, longitudinaliter creberrimè sulcatâ; margine valdè flexuoso; long. 1⅜; lat. 14⁄8 paulo minus; poll.
Habitat in freto Magellanico (Port Famine). Mus. Brit., nost., Brod.
This shell, which was dredged up from deep water in the bay of Port Famine, attached to stones, is not a common shell in the Strait.
19. Terebratula Sowerbii.
T. testâ subrotundâ, planiusculâ, subfuscâ, longitudinaliter radiatim transversim substriatâ, medio supernè depressâ, infra convexâ, subglabrâ; margine utrinque crenulato, medio glabro; long. 17⁄16; lat. 7⁄16 paulo plus; alt. 11⁄16 poll.
Habitat in freto Magellanico. Mus. nost., Geo. Sowerby.
20. Chiton setiger.
C. testâ ovali, anticé subattenuatâ; valvis subdentatis, tenuiter concentricè striatis, anticâ 10-radiatâ, posticâ lævi, parvulâ; areis lateralibus striis duabus elevatis marginalibus; ligamento marginali lævigato, setigero; long. 2⅜; lat. 1⅜; poll.
Habitat ad oras insulæ Tierra del Fuego et in freto Magellanico. Mus. Brit., nost., Brod.
Shell ovate, rather attenuated towards the anterior end, generally of a light blue-green colour, variegated with markings of dark slate. Valves slightly beaked with minute concentric striæ, the lateral compartments with two marginal ridges, which in some specimens are granulose, in others smooth. The anterior valve has eight, besides two marginal, ridges of the same character; the posterior valve is very small and smooth. Border coriaceous, and set with bristles produced from three rows of tufts or pores. In some of the specimens in my possession the bristles are rubbed off.