. Bulletin of the British Museum (Natural History), Geology. 260 R. A. FORTEY & R. M. OWENS Didymograptus (Didymograptellus) sp. (Fig. 114) Occurrence. Fennian, Bergamia rushtoni Biozone, Pontyfenni Formation; loc. 23, Pontyfenni. Material. One specimen, Q5170. Discussion. This incomplete specimen is worth noting as a rare example of a pendent didy- mograptid from below the Llanvirn in Wales. It is not possible to determine it on the basis of so little material, and because the proximal part is not well preserved. It does, however, apparently show a high origin of th 1i and is therefore to
. Bulletin of the British Museum (Natural History), Geology. 260 R. A. FORTEY & R. M. OWENS Didymograptus (Didymograptellus) sp. (Fig. 114) Occurrence. Fennian, Bergamia rushtoni Biozone, Pontyfenni Formation; loc. 23, Pontyfenni. Material. One specimen, Q5170. Discussion. This incomplete specimen is worth noting as a rare example of a pendent didy- mograptid from below the Llanvirn in Wales. It is not possible to determine it on the basis of so little material, and because the proximal part is not well preserved. It does, however, apparently show a high origin of th 1i and is therefore to be assigned to Didymograptellus. The sicula is only about 1mm long, but may not be preserved distally; stipes expand to 1 mm in width; three thecae in 2mm at the distal end indicate a probable mature thecal spacing of 14-15 in 10mm, which is like D. bifidus (Hall). Stipe width is more like that of D. protobifidoides Boucek 1973. Small, distorted pendent didymograptids from Aber Mawr, Ramsey Island (loc. 62), are also late Arenig, but are not specifically Fig. 114 Didymograptus {Didymograptellus) sp. Upper Arenig (Fennian), B. rushtoni Biozone, Pontyfenni Formation, loc. 23, x 10, Q5170. Subgenus EXPANSOGRAPTUS Boucek & Pribyl 1953 [= Extensograptus Bou5ek & Pribyl 1953a: 267 (presumably a mis-spelling, repeated in error by Bulman, 1970: V104).] Type species. Graptolithus extensus Hall 1865. Didymograptus (Expansograptus) hirundo Salter 1863 (Figs 115, 116, 117,120c) 1863 Didymograptus hirundo Salter: 137, fig. 13f. 1870 Didymograptus patulus Hall; Nicholson: 339-341; pi. 7, fig. 1 \_non text-fig. 1]. 1898 Didymograptus patulus Hall; Elles: 504-506, figs 22-23. 1901 Didymograptus hirundo Salter; Elles & Wood: 15-17; pi. 1, figs 5b, c [?no« fig. 5a]. 71934 Didymograptus hirundo Salter; Hsu: 26; pi. 1, figs 8a-d. 1936 Didymograptus hirundo Salter; Bulman (pars): text-fig. 25e [?won fig. 25f]. 1937 Didymograptus hirundo Salter; Monsen: 120-121; pi. 15,
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