Janira affinis Tuomey & Holmes, 1855
TUOMEY, M. & F. S. HOLMES. 1855-1856. Pleiocene fossils of South Carolina. Russell and Jones, Charleston, South Carolina, 152 p. [p. 26, pl. 8, figs. 5, 6]
«JANIRA AFFINIS.— (New Species.)
PLATE VIII., FIGS. 5 AND 6. P. testa subrotunda, tenui; valva inferiore, convexa aequilaterali, extus laevigata, intus binis radiatim costata; auriculis sub-aequalibus.
DESCRIPTION.— Shell almost circular, thin; lower valve convex, equilateral; smooth on the outside, with radiating undulations or obsolete ribs, striated concentrically; on the inside rayed with narrow ribs in pairs; ears nearly equal. The ribs on the inside correspond with the intermediate spaces of the obsolete ribs on the outside. The buccal ear is slightly expanded and crossed by undulating striae, and with an obtuse ridge terminating in the sinus. Although but a single lower valve has been found, the wide channel and corresponding ridge, on the outside of the buccal ear, are sufficient to refer it to the genus JANIRA. The thinness of the shell and interior costee give it some resemblance to P. MORTONI, but it is separated from it by the sinus for the byssus, and greater convexity of the shell. It also resembles J. ZICZAC, of the coast of Florida; the latter, however, has the lower valve more convex, the umbones more prominent, and the flattened external ribs better defined, and marked by an impressed line towards the pallial margin. The genus JANIRA commenced its existence in the ocean of the cretaceous period, is found in the tertiary, and is still an inhabitant of the seas of warm and temperate climates. Both the tertiary and recent species are of greater size than those of the cretaceous. PLATE VIII., FIG. 5. Under side of lower valve, natural size. " 6. Interim of same. LOCALITY. Smith's, Goose Creek. Museum, College of Charleston, S. C.»
MICHAEL TUOMEY & FRANCIS SIMMONS HOLMES, 1855
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M. Tuomey & F. S. Holmes, 1855-1856, plate 8.
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