Pecten deformis Tate, 1887
TATE, R. 1887. The Lamellibranchs of the Older Tertiary of Australia, Part II. Transactions and Proceedings and Report of the Royal Society of South Australia, 9: 142-189. [p. 185, pl. 18, fig. 4]
«Pecten deformis, spec. nov. Plate xviii., fig. 4.
Triangularly ovate, compressed, obliquely extended posteriorly and inequilateral; in the young state regular, subequilateral.
The young regular stage of growth is seen for about 30 millimetres from the umbo; is ornamented with about 50 radial subacute narrow ribs, usually grouped in threes, the middle one being the larger, and with quincuncially arranged depressions between the ribs. The older stage of growth is marked by the sudden irregularity of general growth and change of ornament — the radial ridges becoming almost obsolete, and strong growth folds and concentric striae developed. The ears are unequal, the proximal portions radially ribbed and shagreen sculptured, the distal portions irregular and inornate. Dimensions.— Umbo-ventral and antero-posterior diameters, 47 millimetres. Locality.— Upper beds at Muddy Creek. This species, which is related to P. consobrinus, Tate, may prove to belong to Hinnites, but at present the left valves only have been obtained.» RALPH TATE, 1887
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R. Tate, 1887, plate 18.
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