1864.] LAWSON ON CANADIAN PERNS. 285 



and other American pteridologists think it quite distinct. Its most 

 obvious characters are — ^1.) The tapering form of the lower part of 

 the frond (ahhough there is also a form o^ L. Thehjpteris having 

 this peculiarity ; (2.) sori few, mostly near the base of the pin- 

 nules, and not confluent, not overlapped by a recurved margin ; 

 (3.) veins of the pinnules simple, not forked. The outline of the 

 frond must not be depended upon, as the Scotch and Irish L. 

 Thely2^teris is narrowed at the base Hke L. Nov-Eboracensis, 

 This species is allied to L. montana, Moore [Oreopteris, Bory.) 



POLYSTICHUM. 



P. angidare, ft. Braunii. — Frond soft, herbaceous, lanceolate, 

 bipinnate ; pinnules stalked, serrate ; the small teeth tipped by soft 

 bristles .; stipe and rachis scaly throughout ; In the Canadian 

 plant the scales of the rachis are larger than in the typical P. angu- 

 lare of England, from which it may be sperifically distinct: As- 

 jpidium Braunii, Spenner. Aspidlum acuhatum var. Braunii, A. 

 Gray, Man. Bot., p. 599, A. aculeatum, Abbe Provancher; Har- 

 rington, Cape Bon-Ami and Dartmouth, N. fork, Gaspe, John 

 Bell, B. A. ; base of Silver Mountain, W. S. M. D'Urban. 



P. Lonchitis, Roth. — Frond rigid and shining, linear-lanceolate, 

 simply pinnate ; pinnas scythe-shaped, auricled, spino-e. Polys- 

 tichum Lonchitis, Roth, Moore, J. Sm., &c. Polypodiwni Lon- 

 chitis^ Linn. Lapidium LoncJiitis, Swartz, Schk. — Limestone 

 rocks, Owen Sound, C. W., 1859, Rev. Professor Hincks. 

 Professor Hincks has also kindly furnished me with spcimens from 

 the above locality. Woods, southern shore of Lake Superior and 

 north-westward, Professor Asa Gray, in Man. ; British America, 

 Professor Wood in Class Book. It will be observed that Pro- 

 fessor Hincks's station is the only definite Canadian one with 

 which we are acquainted. Mr. T. Drummond found this fern on 

 the Rocky Mountains many years ago. 



P. acrostlchoides, Schott. — Frond pale green shining, long and 

 narrow, linear-lanceolate, simply pinnate ; pinnae long and narrow, 

 linear-lanceolate, shortly stalked, auricled anteriorly at the base, 

 more or less distinctly serrate, with hair-tipped teeth ; fertile (upper) 

 pinnje slightly contracted, covered beneath by the large confluent 

 son stipe profusely chaff'y, with pale scales. Polystichum acros- 

 tlchoides. Schott, J. Sm. Aspio'ium acrostichAdes, Swartz, 

 A. Gray, Eaton. Aspid. aiiricidatum, Schk. Nephrodium 

 acrostlchoides, Michx. — Abundant in the woods a few miles from 



