Indopecten serraticosta (Bittner, 1899)
BITTNER, A. VON. 1899. Himálayan Fossils. Part 2. Trias-Brachiopoda and Lamellibranchiata. Palaeontologia Indica [series 15], 3 (2): 1-76, pls. 1-12. [p. 50, pl. 8, figs. 12, 13; pl. 10, fig. 26]
1899 Lima serraticosta Bittner, 1899
1924 Pecten (Aequipecten) subserraticosta Krumbeck, 1924 [partim]
1924 Pecten (Aequipecten) subserraticosta Krumbeck, 1924 [partim]
A. von Bittner, 1899, plate 8.
A. von Bittner, 1899, plate 10.
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«This form belongs perhaps rather to Lima than to Pecten. In favour of this
view are its oblique shape, the steep slope of one (anterior?) side, and the apparently slight development of the ears. The proportionately thick shell is raised, at intervals so as to form seven high-roof-like ribs, on whose blunt edges the striae of growth, elsewhere very fine and crowded, become elevated into rows of small blunt tubercles which give a serrated appearance to the ribs. The three middle and strongest ribs only possess one row of such serrations on their crests, the weaker ribs, succeeding on each side outwardly, show on the other hand besides the chief row on the crest, one or two weaker rows of a similar kind, which rise constantly on the outer side of each rib. The posterior of the three middle ribs also possesses a trace of a similar accessory row of serrations near the lower margin of the shell, and here it aslo lies on the outward side. Nothing definite can be affirmed as to the shape of the ears in consequence of their imperfect preservation; the posterior ear appears to be sharply marked off from the shell. The cast of this thick-shelled species is distinguished by the fact that on it (Fig. 13) the ribs stand out much more cleary from the furrows than is the case on the surface of the shell itself. I know of no species which could be closely oompared with this form, which generically remains, it is true, somewhat uncertain. Its striking shape justifted, I think, a description of it so far as it was possible to make out. Locality.— Collected by Diener in the so-called 'Tropites beds' of the Bambanag section (II). An identical, or at least very closely related form seems also to occur in still higher beds, as the cast (PI. X., fig. 26) shows. The latter is derived from the so-called 'Corbis-zone' of Griesbach or Diener's Sagenites beds, succeeding the horizon of Spiriferina Griesbachi, likewise from the Bambanag section (II). The typical bivalve of the Sagenites bed occurs, however, also below the beds with Spiriferina Griesbachi, as will be shown further on (cf. Anodontophora Griesbachi).» (a²) From the Horizon of Spiriferina Griesbachi,and the Sagenites beds succeeding them.
ALEXANDER VON BITTNER, 1899
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