Nine agnostoid species from late Cambrian (Paibian: Steptoean) boulders from the Cow Head Group in western Newfoundland fall into three biostratigraphically distinct faunas. The pan class="named-content genus-species" id="named-content-1">Glyptagnostus reticulatuspan> Fauna contains only the eponymous species and correlates with the lower part of the Paibian and the basal Steptoean of North America. The “pan class="named-content genus-species" id="named-content-2">Innitagnostuspan>” pan class="named-content genus-species" id="named-content-3">inexpectanspan> Fauna is more diverse and likely correlates into part of the lower Steptoean pan class="named-content genus-species" id="named-content-4">Aphelaspispan> Zone of western North America. The youngest fauna, the pan class="named-content genus-species" id="named-content-5">Acmarhachis kindleipan> n. sp. Fauna, also includes species of pan class="named-content genus-species" id="named-content-6">Homagnostuspan> and pan class="named-content genus-species" id="named-content-7">Pseudagnostuspan>, as well as a second new species of pan class="named-content genus-species" id="named-content-8">Acmarhachispan>, pan class="named-content genus-species" id="named-content-9">A. whittingtonipan>. It probably correlates with the pan class="named-content genus-species" id="named-content-10">Dunderbergiapan> Zone (mid-Pabian and mid-Steptoean) of the western United States. The Laurentian species pan class="named-content genus-species" id="named-content-11">Acmarhachis typicalispan> pan id="xref-ref-66-1" class="xref-bibr">Resser (1938)pan> and pan class="named-content genus-species" id="named-content-12">A. acutapan> (pan id="xref-ref-33-1" class="xref-bibr">Kobayashi, 1938pan>) are evaluated from restudy of type material, and types of “pan class="named-content genus-species" id="named-content-13">Innitagnostuspan>” pan class="named-content genus-species" id="named-content-14">inexpectanspan> (pan id="xref-ref-33-2" class="xref-bibr">Kobayashi, 1938pan>) from British Columbia are also reillustrated.
