. Brachiopod genera of the suborders Orthoidea and Pentameroidea. Orthoidea; Pentameroidea; Paleontology -- Paleozoic. 100 GENERA OF THE SUBORDERS ORTHOIDEA AND PENTAMEROIDEA process comes to resemble that of Plectorthis, hence this is no serious objection to placing Austinella near D'lnorthis. The brachiophores appear to be of the Dinorthis type and are supported chiefly by adventitious shell substance. When Foerste named the genus in 1909 he stated in the introductory sentence that "Dinorthis scovillei belongs to a group of species typified by Orthis kanka- kensis, McChesney and includi
. Brachiopod genera of the suborders Orthoidea and Pentameroidea. Orthoidea; Pentameroidea; Paleontology -- Paleozoic. 100 GENERA OF THE SUBORDERS ORTHOIDEA AND PENTAMEROIDEA process comes to resemble that of Plectorthis, hence this is no serious objection to placing Austinella near D'lnorthis. The brachiophores appear to be of the Dinorthis type and are supported chiefly by adventitious shell substance. When Foerste named the genus in 1909 he stated in the introductory sentence that "Dinorthis scovillei belongs to a group of species typified by Orthis kanka- kensis, McChesney and including also Orthis whit- fieldi, N. H. ; This statement implied, if it did not definitely say, that O. kankakensis is the genotype of Austinella. Evidently Bassler so inter- preted Foerste's words, because O. kankakensis is desig- nated as the type in the Ordovician-Silurian Index, p. 1002.*- Later, however, Foerste''^ stated that "Aus- tinella scovillei is regarded as the genotype of the pro- posed group, ; As we have already noted, Foerste selected the genotype in 1909 and this selection must stand. Genus Holtedahl 1916 Holtedahl, Videns. Skrift., I. Klasse, 1915, no. 12, 1916, p. 43, pi. 7, figs. 1, 2. Genolectotype (Opik).—P. concava Holtedahl 1916 (non Strofhomena concava Schmidt; see Opik, Acta et Comment. Univ. Tartuensis, A, vol. 17, pt. 1, 1930, p. 57). Original description.—General form as in Strofho- mena and Strofhonella but differs distinctly in interior characters of dorsal valve, the cardinal process being not bilobed but as in the Orthida: simple, having the shape of a short vertical plate, posteriorly united with the crural plates, which end rather abruptly. The cardinal process is supported by a faint median elevation in the valve stretch- ing for some distance anteriorly. Interior of ventral valve not known. Geologic range.—Lower Ordovician (Stage 3) of Norway. The only species is the genot
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