172. P. navicularis, (Lehm& Lindb.) Lindb.
Observatory Inlet, British Columbia. (Dr. Scouler.) Vancouver Island. (Dr. Lyall.) Chilcoot, Alaska. (Krause.) On trees at Hastings, Burrard Inlet, B.C.; quite common on boulders in woods, on rocks, on old logs, and on trees in swamps at Victoria and on trees at Comox, Vancouver Island; on trees and rocks, Salt Spring Island, Gulf of Georgia; and on rocks at Yale, Fraser River, B.C. (Macoun.) On trees, Alert Bay, Vancouver Island. (Dr. G. M. Dawson.) Hot Spring, Alaska. (Evans.)
173. P. platyphylla, (Linn.) Lindb.
A very common species throughout eastern Canada.
At the base of trees, Canaan Forks, and Never's Rapids, Queen's Co., N.B. (Moser.) On rocks, North West Arm, Halifax,
N.S.; on trees at Yarmouth, N.S.; on rocks and trunks at Mar-garee, Cape Breton Island, N.S., July, 1898; on trees at Grand Etang, Gaspé Co., Que.; on trees at Ottawa, Ont.; on rocks at Sudbury Junction, Algoma; on trees and rocks at Belleville, Hastings Co., Ont.; on rocks at Owen Sound, Ont.; Nipigon River, Ont.; on trees, Queenston Heights, Ont., 1901; on trees in woods, Câche Lake, Algonquin Park, Ont., June 6th, 1900. (Macoun.) On trees, River Rouge, Argenteuil Co., Que. (D'Urban.) On Missinaibi River, Algoma. (Dr. R. Bell.) Guissen, Alaska.
P. platyphlloidea, Pearson's List, No. 20.
On wet rocks, Moose Mountain, Elbow River, alt. 6,000 feet, Rocky Mountains, July, 1897; on rocks, Selkirk Mountains, and in Roger's Pass, B.C., 1890; on trees along the Fraser River, near Mission, B.C.; on rocks at Yale, Fraser River, B.C., 1872; on damp rocks, Eagle Pass, and on rocks at Revelstoke, and Robson, Columbia River, B.C.; on stones in the Colquitz River and on young firs near Victoria, Vancouver Island. (Macoun.) Sitka, and Yakutat Bay, Alaska. (Evans)
175. P. Roellii, Steph., Bot. Centralb. 45, 1891.
On rocks, Pass Creek, Robson, B.C., June, 1890; on damp rocks in a ravine at Craigflower, near Victoria, and on rocks near the waterworks, Victoria, Vancouver Island, May 30th, 1893; on rocks on the summit of Mount Benson, near Nanaimo, Vancouver Island, June 8th, 1887; on rocks, Salt Spring Island, and at Nanaimo River, Vancouver Island, May, 1887; on rocks above Yale, B.C., May 17th, 1875. The latter specimen was referred to P. laevigata by Pearson, but after reading Dr. Howe's remarks in his work on the Hepatics of California we place it under this species. (Macoun.) On wet cliffs, Chilliwack River, B.C., 1901. (J. M. Macoun.)
176. P. pinnata, Linn.
On stones in Trent River, below Heely Falls, Northumberland Co., Ont; on stones in a creek, Mr. Roy's farm, near Owen Sound, Ont.; on stones in brooks, Kakabeka Falls, west of Fort William, Lake Superior; on stones in Bonnechère River, Golden Lake, Renfrew Co., Ont.; on the bases of trees subject to flood, shore of Lake Duchesne, above Britannia, near Ottawa, Ont., Oct. 27th, 1900. (Macoun)