. Annual report. New York State Museum; Science; Science. GRAPTOLITES OF NEW YORK, PART 2 193 pal criterion of distinction between the two species, we have preferred to associate the present variety with G . quadri-mucronat u s. Glossograptus quadrimucronatus (Hall) var. cornutus no v. Plate 27, figures 8-10 The rhabdosomes of this variety are of medium size (average length 25 mm, rarely surpassing 30 mm, and width mm), beginning with a rounded sicular extremity mm wide ; rapidly attaining the full width (in space of about 4 mm). Sicular extremity buttonlike and furnished with two lo
. Annual report. New York State Museum; Science; Science. GRAPTOLITES OF NEW YORK, PART 2 193 pal criterion of distinction between the two species, we have preferred to associate the present variety with G . quadri-mucronat u s. Glossograptus quadrimucronatus (Hall) var. cornutus no v. Plate 27, figures 8-10 The rhabdosomes of this variety are of medium size (average length 25 mm, rarely surpassing 30 mm, and width mm), beginning with a rounded sicular extremity mm wide ; rapidly attaining the full width (in space of about 4 mm). Sicular extremity buttonlike and furnished with two lonof, hornlike curved lateral spines and a strong virgella, all of which show great individual differences in develop- ment. Nemacaulus very thin and hairlike. Test thick. Sicula 2 mm long. Thecae numbering 10 to 12 in to mm (25-30 in space of 1 inch), one third as wide as long, inclined 300 to the axis, overlap- ping one half their length. Aper- ture rectangular to axis, broad and slightly concave. Apertural spines as long as aperture, straight, and directed horizontally. Tl-lit: -uanVtv h a Q ll^en fniinrl F'S- 338-42 Glossograptus quadrimucronatus var. 1 HIS VarieC) lias UCeil IOUIia cor'nut°us nov. Fig. 338 Rhabdosome. Fig. 339 Portion of rhabdosome showing; both apertural spines of thecae. Fig. 34o Only at the Rural Cemetery near Sicular end, showing sicula, first theca and large^ lateral spines. ?> ?* Fig. 341 Sicular extremity with three large spine?. Pig. 342 a 11 1 ..i Growth stage of rhabdosome with three thecae. Figures 338, 33o, Albany, but there in great num- 34i are enlarged x s: figures 3+o, 342 x 7 ber and excellent preservation. Its most striking features are the long apertural spines and the strong, frequently curved lateral spines of the sicular end, in support of which the test of that whole part has become so much thickened that the extremity frequently stands out buttonlike. From. Please note that these images are extracted from scanned page images that
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