Narrative of the surveying voyages of his majesty's ships Adventure and Beagle (vol.1): between the years 1826 and 1836 : describing their examination of the southern shores of South America, and the Beagles's circumnavigation of the globe

CATALOGUE — SHELLS. 549 described has a rounded form ; the bows or front being rather elegantly and finely laraellated in a wavy form ; the colour of the hinge is red, and the inside is generally of a brownish purple ; in some it has a more yellow tinge. 13. Arca pectinoides. A. testd auriciilatd, cordatd, ventiicosd, multi'costatd, transversivi striatd, alba, epidermide rufo nigricante, pilosdj umbonibus sub- approximatis, incurvatis, 7nargi7ie crenulato; long. 1 ; lat, 1^ ; poll. Habitat ad Rio de Janeiro. Mus. Brit., nost., Brad. 14. NUCULA STRIATA. N. testd striatd, subtumidd, crassd, sub-trigond, albd; latere antico productiori, sub-rostrato ; long. J^ ; lat. f ; poll. Habitat in mari alto circa oras Patagonicas. Mus. nost. Taken by a dredge in 40 fathoms water, 20 miles from the coast of South America, in the neighbourhood of Port Sta Elena. 15. MODIOLA SINtrOSA. M. testd ventricosd, subovatd, longitudinaliter striatd; intus irides- cente, margine sinuoso, eindermide fused ; long. -^^ ; lat. Wfofe; poll. Habitat ad littora Brasilice (Santos). Mus. nost. 16. Pecten Patachonicus. P. testd sub-cequivalvi, brunned, longitudinaliter creberrime elevalo- radiatd; intus albidd, longitudinaliter sub-radiatd ; long. 2^; lat. 2^; poll. Obs. auribus incequalibus. Habitat infreto Magellanico passim. Mus. nost. 17. Pecten vitreus. P. testd subcequivalvi, translucente, longitudinaliter multi-sulcatd sulcis convexis Jlavidulis, valvd inferiore pallidiori ; long, l^^g- lat. 1|; poll. Obs. Auribus incequalibus. Habitat ijijreto Magellanico passim. Mus. nost. This shell is found attached to the leaves of the Funis giganteus, and, with other Mollusca, is the food of the Steamer or Race-horse Duck {Micropterus brachyptera and M. Patachonica).