Pecten circularis cornellanus F. & H. Hodson, 1927
HODSON, F., H. K. HODSON & G. D. HARRIS. 1927. Some Venezuelan and Caribbean mollusks. Bulletins of American Paleontology, 13 (49): 1-80, pls. 1-40. [p. 26, pl. 14, fig. 2; pl. 15, figs. 3, 10; pl. 16, fig. 3]
«Pecten circularis cornellanus F. and H. Hodson, n. subsp.
Pl. 14, fig. 2; pl. 15, figs. 3, 10; pl. 16, fig. 3.
This is a subspecies in which the ribs in the adult stage have steep, almost vertical, sides instead of the more sloping sides of the species, sensu stricto, and of the other subspecies, venezuelanus; the sides are even somewhat excavated in many cases, and the tops of the square ribs project slightly over them. The interspaces appear almost square; as in the related forms, the concentric growth lines swing down in the interspaces and swing up on top of the ribs. Like the other subspecies, this is an exceedingly abundant and variable form. The square shape of the ribs may be maintained entirely to the margin or it may give way to ribs with slightly sloping sides. Generally, this subspecies is somewhat smaller than P. circularis venezuelanus, averaging about 30-35 mm. in altitude, although some specimens exceed 40 mm.
This subspecies may be equivalent in part to P. levicostatus Toula,¹ but his figures are so poor that it is impossible to be sure. His type (fig. 4) has rounded ribs and is not to be confused with the square ribs so common in this Venezuelan subspecies. Toula's species may be only a variation or variety of P. circularis. Age: Miocene. Locality : Common in the State of Falcon ; Gatun, C. Z.; locality numbers 68A, 69, 70A, 70C, 78, 79, 80 (?), 81, 82, 83, 83A, 83B, 88A, 93, 94 (and variations), 95, 97, 109, 120, 121, 125, 127, 157, 182, 184, 185, 186, 193 (variation), 193A, 215, 216, 217, 219 (variation), 222, 224, 242, 307, 1007, 1010, 1027, 1029, 1030, 1031, 1033, 1066, 1078, 1111, 1115, 1232, 1255, 1256, 1332, 1447 (and variations), 1855, 1871, 1872, 1911.» ¹ Jahrbuch der k.-k. Geol. Reichsanstalt, Wien, 1909, vol. 58, (1908), p. 713, pl. 26, figs. 4-6.
FLOYD HODSON & HELEN K. HODSON, 1927
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F. Hodson, H. K. Hodson & G. D. Harris, 1927, plates 14, 15, 16.
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