. Annual report. New York State Museum; Science; Science. 288 NEW YORK STATE MUSEUM increasing, however, at end of first theca to 2400; branches combined in a gentle, flexuous curve to their extremities, averaging in width about mm. Thecae 30 or 32 in 25 mm; adnate to the coenosarcal canal, with straight or very slightly convex margins and slightly inclined apertural edge. The affinities of this form are distinctly with S. pertenuis Lap- worth and its associates, S. explanatus and S . n i t i d u 1 u s. From all these, however, it differs in absence of secondary branches and in general for
. Annual report. New York State Museum; Science; Science. 288 NEW YORK STATE MUSEUM increasing, however, at end of first theca to 2400; branches combined in a gentle, flexuous curve to their extremities, averaging in width about mm. Thecae 30 or 32 in 25 mm; adnate to the coenosarcal canal, with straight or very slightly convex margins and slightly inclined apertural edge. The affinities of this form are distinctly with S. pertenuis Lap- worth and its associates, S. explanatus and S . n i t i d u 1 u s. From all these, however, it differs in absence of secondary branches and in general form of polypary. Horizon and locality. Lower Dicellograptus zone, Stockport, N. Y. Gurley remarks : To the above description I may add that some specimens indicate that the primary branches give origin to secondary ones, probably from the athecaphorous margin. No figures of this species have thus far been published ; nor were any found accompanying Gurley's manuscript. I therefore insert here drawings of those specimens which were found in the Stockport collection and labeled as Stephanograptus exilis as the original figures of the species. One of these [pi. 17, fig. 4]' shows the proximal parts of the secondary branches and having been marked for illustration is evidently the specimen to which Gurley had reference in the before-quoted note. Another speci- men from Stockport [pi. 17, fig. 7], which apparently had been overlooked by Gurley, retains the secondary branches to a considerable length on both / 203 Fk*. 202, 203 Nemagraptus exilis (Lapworth). Fig. 202 Enlargement (x 5) of the type. Fig. 203 Proximal part of another specimen from Stockport, also x 5 Much more complete material of this interesting form has been fur- nished us by the shales at Glenmont [see pi. 17, fig. 3, 5, 9]. This, as well as some of the Stockport material, suggests the following supplementary notes:. Please note that these images are extracted from scanned page images that may have been digita
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