Platyschisma M'Coy, 1844

Australian Carboniferous species. Platyschisma lingua n.sp., from 'Rangari'; Platyschisma vitrea n.sp., from 'Marohn'.

Remarks. The Early Permian species Platyschisma allandalensis Mitchell (1922) and the form referred to Platyschisma oculus Sowerby by de Koninck (1876) are large in size. The width of P. allandalensis is lO 5 mm. The original figures of P. allandalensis does not show the detail of the shell, and its exact locality is not known. Comparison of P. allandalensis with the type species, Platyschisma helicoides Sowerby, suggests that P. allandalensis is better referred to Keeneia of Etheridge (1902).