. Bulletin - New York State Museum. Science. SOME NEW DEVONIC FOSSILS 257 This species with which I was at first disposed to identify the shells in hand is usually of small extended form with a very regu- larly convex ventral valve and broadly rounded plications. Though distinct in outline and contour it often represents the aspect in external and internal surface of S. c y m i n d i s . S. d e c h e n i Kayser [see Kayser. Fauna d. aeltest. Devon- Ablag. des Harzes. 1878. p. 165, pi. 22, fig. i, 2]. This is a very large species but its smaller expressions, of which I have specimens from the K


. Bulletin - New York State Museum. Science. SOME NEW DEVONIC FOSSILS 257 This species with which I was at first disposed to identify the shells in hand is usually of small extended form with a very regu- larly convex ventral valve and broadly rounded plications. Though distinct in outline and contour it often represents the aspect in external and internal surface of S. c y m i n d i s . S. d e c h e n i Kayser [see Kayser. Fauna d. aeltest. Devon- Ablag. des Harzes. 1878. p. 165, pi. 22, fig. i, 2]. This is a very large species but its smaller expressions, of which I have specimens from the Kellerswald, are like S. c y m i n d i s in degree of plication, though here it is the second rather than the first pair of lateral plications that dominate the rest. The ventral valve is uniformly convex but the umbo is not strongly arched. S. n e r ei Barrande [as identified by Walther]. Specimens from the upper Coblentzian of Marburg very like this shell in general aspect are somewhat more numerously plicated but a distinctive feature lies in the very long dental plates such as are present in S. lateincisus. Lower Devonic. Presque Isle stream, Chapman Plantation, Me. Spirifer cymindis var. sparsa nov. Associated with S. cymindis and quite as abundant, is a shell distinguished in gross by its sparser plication. Our material here. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original New York State Museum; New York State Museum. Albany : New York State Education Dept


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Keywords: ., bookcentury1800, bookdecade1880, booksubjectscience, bookyear1887