. Annual report. New York State Museum; Science; Science. 3IO NEW YORK STATE MUSEUM dently caused by a slight torsion of the branches, which probably is the main differential character of the variety. Dicellograptus sextans var. perexilis nov. Plate 19, figure 2 Cf. Dicellograptus sextans var. tenuibrac hiatus Lapw. Roy. Soc. Can. Trans. 1887. 4: 179 In a layer of the Normanskill shale at Mt Moreno D. sextans is represented by a variety, the most striking feature of which is the extreme thinness of its branches, the width of the latter amounting to no more than .2 mm. Besides, the angle of div
. Annual report. New York State Museum; Science; Science. 3IO NEW YORK STATE MUSEUM dently caused by a slight torsion of the branches, which probably is the main differential character of the variety. Dicellograptus sextans var. perexilis nov. Plate 19, figure 2 Cf. Dicellograptus sextans var. tenuibrac hiatus Lapw. Roy. Soc. Can. Trans. 1887. 4: 179 In a layer of the Normanskill shale at Mt Moreno D. sextans is represented by a variety, the most striking feature of which is the extreme thinness of its branches, the width of the latter amounting to no more than .2 mm. Besides, the angle of divergence of the branches is constantly smaller (2700 in the proximal \ art and 2400 ultimately) and the branches are more flexible. As a result of these characters the habit of the variety is entirely different from that of the typical sextans, but the form and arrangement of the thecae and the presence of mesial spines on all thecae place Fig. 233 Dicellograptus sextans var. perexilis . , ? nov. Typical specimen. x5 it With that SpeClCS. From the narrow variety exilis this one is distinguished by its still smaller width (but half that of exilis) and the smaller angle of divergence. D. sextans var. p e re x i 1 i s is associated with Didymogr. sag- itticaulis, Nemagr. gracilis, and Lasiogr. mucronatus. Dicellograptus moffatensis (Carruthers) var. alabamensis nov. , Plate 20, figures i, 2 Didymograptus moffatensis Carruthers. Roy. Soc. Edinburgh Proc. v. i, pt 2. 1858. , fig. 3 Dicellograptus moffatensis Elles & Wood. Monogr. Brit. Grapt. pt 4 (Pal. Soc. 1904) ; pi. 23, fig. ia-f Description. Branches of rhabdosome, as a rule, markedly straight,. 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. Albany : University of the State of New York
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