184 MACOUN AND BUEGESS ON 



Pellaa gracilis is a very delicate, non-evergreen, little fern, 3 to 10 inches high, with 

 fronds in general appearance a good deal like those of Gryptogramme acrostichoides, growing 

 in the crevices of damp, shaded, calcareous rocks. The fertile and sterile fronds are some- 

 what unlike, — the former, which are the tallest, having distinct, linear-oblong, almost 

 entire ultimate segments, of which the terminal arc much the longest, while in the latter 

 they are decurrent, ovate or obovate, and cut or toothed. Root-stock slender, creeping, 

 nearly naked ; stalks slender, 1 £ to 6 inches long, brownish or pale-straw coloured, some- 

 what polished and sparingly chaffy at the base ; fronds (including both fertile and sterile) 

 smooth, ovate or ovate-oblong in outline, very delicate, and bi-tripinnatifid ; veins mostly 

 only once forked ; indusia broad, remaining rolled over the sori until they are ripe. 



In some specimens of this fern from Owen Sound, Out., the ultimate segments of the 

 fertile fronds are almost narrowly linear, while in some from Ottawa, Out., they are ovate, 

 and the terminal ones but very little the longer. 



This fern occurs in British America from Labrador to British Columbia, though it is 

 by no means a very common species. Morris Falla , Restigouche, and Grand Falls, St. 

 John, N. B. — Fowler. "Woodstock, N. B. — P. Jack. On crystalline limestone, near the Lake 

 of Three Mountains, River Rouge, Que. — W. S. M. If Urban. Cacouna, Que.—/. W. Daiv- 

 son. Riviere du Loup, en bas, Que. — Dr. Thomas. Crevices of limestone rocks near Hem- 

 lock Lake, Ottawa, Ont.—J. Fletcher. Lakefield, Out.— Mrs. Traill. Canada (G oldie), to the 

 Saskatchewan (Drummond), in Hook., Fl. Bor.-Am. Crevices of rocks near L'Anse a Fallon, 

 Cape Rosier, and Ste. Anne des Monts River, Gaspe, Que. ; limestone rocks along the River 

 Moira, near Belleville, Out. ; crevices of rocks, Foster's Flats, below the Whirlpool, Niagara 

 Falls, Out. ; along the Kaministiquia River, below the Kakabeka Falls, Out., and on ledges 

 at the falls ; under the cliffs at Red Rock and near Nipigon Station, on the Canada Pacific 

 Railway, Out. ; crevices of the Huronian slates seventeen miles from Michipicotin, on the 

 Magpie River Road, Out. ; Peace River Pass, Rocky Mountains, N. W. T. — Macoun. 



* * Fronds leathery, A _ eins obscure. 



2. — P. atropurpurea, Link; (Clayton's Cliff-Brake), Gray, Man., 660. Lawson, Can. 

 Nat., I, 212. Hook.and Baker, Syn. Fil., 14*7. Macoun's Cat., No. 2289. Watt, Can. Nat., 

 IV, 363. Eaton, Ferns of N. A., II, 61. Underwood, Our Nat. Ferns, etc, 93. 



Pteris atropurpurea, L. Pursh, II, 668. 



Platyloma atropurpurea, J. Smith. 



Allosorus atropurpurea, Kunze. Gray, Man., ed. 2nd, 591. 



This evergreen species grows from 2 to 18 inches high and on dry, though shaded, rocks, 

 which are generally calcareous. Rootstock short and chaffy ; stalks clustered, wiry, dark 

 purple, polished, and with usually more or less chaffy hairs on them ; fronds commonly 1 

 to 12 inches long, ovate or oblong-lanceolate in outline, leathery, and pinnate, or near the 

 base, bipinnate ; fertile pinnules and simple pinnae usually acutish and oblong-linear or 

 linear (sometimes two inches long), while the sterile are obtuse and oval or oval-oblong 

 (about half an inch long) ; at the base, the pinnules, of which the terminal are the longest, 

 may be truncate, slightly cordate, or auricled on one or both sides; veins mostly twice 

 forked ; indusia rather broad, but not fully covering the sori. 



Forking pinnules and fronds of this fern are not very rare, and sometimes the auricles 

 at the base of a pinnule are as long as the pinnule itself. A form from near Ashcroft, B. 



