. The Canadian field-naturalist. 120 The Canadian Field-Naturalist [Vol. 66. Paleogeo^raphic map of part of North America during Richmond time showing the locations of the exposures mentioned in the text, and the suggested distribution of land (ruled) and sea (plain). 1. Was- wanipi Lake. 2. Lake Timiskaming. 3. Anticosti Island. 4. Lake St. John. 5. Nelson River. 6. Shamat- tawa River. 7. Lake Winnipeg. 3 Galena limestone. as Richmond (2, p. 186; 6). This means that the Waswanipi Lake exposures carry the area of outcrop of this western (Arctic) type of Richmond 150 miles further east than has
. The Canadian field-naturalist. 120 The Canadian Field-Naturalist [Vol. 66. Paleogeo^raphic map of part of North America during Richmond time showing the locations of the exposures mentioned in the text, and the suggested distribution of land (ruled) and sea (plain). 1. Was- wanipi Lake. 2. Lake Timiskaming. 3. Anticosti Island. 4. Lake St. John. 5. Nelson River. 6. Shamat- tawa River. 7. Lake Winnipeg. 3 Galena limestone. as Richmond (2, p. 186; 6). This means that the Waswanipi Lake exposures carry the area of outcrop of this western (Arctic) type of Richmond 150 miles further east than has hitherto been recognized, and as a conse- quence a correction in the standard paleo- geographic maps of North America for Richmondian time should be made. It is customary ( 3, p. 154) to show a land area from James Bay extending southwest- wards across the International Border. The assumption of such a land barrier is rendered untenable by the reasonable lithologic and faunal correlation of the Richmond limestone from Lake Winnipeg, Nelson River, Lake Timiskaming and Waswanipi Lake. Few faunal and fewer lithological characteristics of the Richmondian beds of southern Quebec and of the Lake St. John outlier recommend them as correlatives of the Liskeard Rich- mond beds of Waswanipi Lake or of Lake Timiskaming. However, further research may still extend the Liskeard sea eastward pos- sibly as far as Anticosti, a prediction made by Twenhofel (8, p. 67) as a result of his finding so great a faunal, though not litho- logic, similarity between the Vaureal forma- tion of Anticosti and the Stony Mountain beds of the Lake Winnipeg area. Such an ex- tension would indicate a land barrier between the Liskeard sea and the St. Lawrence-Cin- cinnati sea. These paleogeographic specula- tions are indicated on the accompanying map. The Lake St. John outlier is shown to be north of this barrier, though it may have lain to the south of it because its fauna is more closely related to that of t
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