Argopecten neahensis (Arnold 1906)
ARNOLD, R. 1906. The Tertiary and Quaternary pectens of California. United States Geological Survey Professional Paper, 47: 1-264, pls. 1-53. [p. 87, pl. 15, figs. 2, 2a, 2b]
1906 Pecten (Plagioctenium) neahensis Arnold, 1906
R. Arnold, 1906, plate 15.
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«Description.— Adult shell averaging about 45 millimeters in altitude, somewhat longer than high, subequivalve, subequilateral, prominently ventricose, especially for about the first 25 millimeters of altitude, after which it is sometimes more compressed; sides concave above; base evenly rounded; margins smooth. Right valve with 19 prominent rounded ribs, separated by somewhat narrower interspaces; surface sculptured by fine inremental lirulae which loop back over the tops of the ribs; hinge line over one-half length of disk; ears subequal; anterior with 4 or 5 prominent radials, posterior with one or two less prominent ones; both ears sculptured by fine incremental lines; byssal notch rather prominent. Left valve a little less ventricose than right and with ribs narrower and more sharply convex above and the interspaces relatively broader; ears as in right valve.
Dimensions.— Alt. 43 mm.: long. 50 mm.: hinge line 28 mm.; diameter 28 mm. This species is probably allied to P. circularis and P. circularis var. aequisulcatus, but may be distinguished by its fewer and narrower ribs and longer hinge line. The type (U. S. N. M. No. 5912) is labeled "Neah Bay, Washington," and was collected by Lieut. J. G. Swan. The beds in the immediate vicinity of Neah Bay were found by the writer to be almost entirely unfossiliferous, so that it is probable that P. neahensis, instead of coming from Neah Bay, comes from some of the fossiliferous strata farther east, possibly from those in the vicinity of Clallam Bay. RANGE
Miocene. Clallam County, near (?) Neah Bay, Washington (J. G. Swan).»
RALPH ARNOLD, 1906
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