. Bulletin - New York State Museum. Science. Spirifer sub c u s p i da t u s lateincisus each side of fold and sinus and they are narrow, round, separated by furrows of similar width. The concentric markings are grov/th lines which may show a tendency to rugosity near the front. 4 Fold and sinus. The sinus is moderately deep and angulated. It is more sharply angulated on the Maine specimens; in some of the German specimens this angulation is apparent only in later growth. The fold is the counterpart of these characters. 5 Internal characters. Most notable independently and in point of agreemen
. Bulletin - New York State Museum. Science. Spirifer sub c u s p i da t u s lateincisus each side of fold and sinus and they are narrow, round, separated by furrows of similar width. The concentric markings are grov/th lines which may show a tendency to rugosity near the front. 4 Fold and sinus. The sinus is moderately deep and angulated. It is more sharply angulated on the Maine specimens; in some of the German specimens this angulation is apparent only in later growth. The fold is the counterpart of these characters. 5 Internal characters. Most notable independently and in point of agreement are the very long dental plates, which diverge rather more in the German than in the American form. In the Hartz specimens these plates lie uniformly in the first radial grooves and hence diverge at the angle of divergence of the radii. In the American shells they are quite as uniformly subparallel to each other and thus are not parallel with the radii but transect the prox- imal end of first sulcus and plication. This is a slight but per- sistent difference. The muscle area in both shells is but faintly defined on the ventral valve. Lozver Devonic. Presque Isle stream. Chapman Plantation, Me. Spirifer cymindis nov. This is a shell belonging to an extensive group of early Devonic species which I presume are all minutely fimbriate (as in S. con- c inn us Hall) though not in all have the surface characters been. 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
