450 A.COTYLEDONOUS PLANTS. 



of a darker green. Sori large, distinct, very dark when ma- 

 ture. 



7. A. goldianum Hook.: frond pinnate; pinna deeply pinnatifid, 

 lanceolate, acuminate ; segments oblong, subacute, somewhat falcate, 

 mucronate-serrate ; sori in rows, one between the midrib and either 

 margin of the segments. A.filiz mas Pursh. 



HAB. Woods. Can. and N. S. July. If. Fern 1 1-23 feet 

 high. Resembles A. cristatmn more than any of our species, 

 but can at once be distinguished by the greater breadth of the 

 frond, giving it a different outline, and by the form of the pinme, 

 which are never broader at base ; the segments also are longer 

 and narrower, and slightly falcate. 



'* Fronds bipinnate. 



8. A. fragile Willd. : frond bipinnate ; pinnules oblong, rather 

 obtuse, incisely serrate or subpinnatifid ; segments subentire ; rachis 

 winged ; stipe chaffy at base. A. tcnvc Pursh. A. atomariuin Willd. 

 Cyathea fragilis Smith. Nephrodium tenue Mich. Atfiyrium fragile 

 Richardson. 



HAB. Moist rocka. N. Y. Ver. Mass. N. to Arc.- Amer. 

 June, July. !. A beautiful little fern, growing in lax tufts, 

 14 inches high. Stipe long and slender, dark coloured and 

 a little chaffy at base. Frond delicate, deep green. Pinnules 

 very variable in shape and in their divisions, some being quite 

 acute, others obtuse and wedge-shaped. Sori large, numerous, 

 pale, near the margins of the segments, Involucre somewhat 

 cyathiform, at length lacerate and reflezed. Our plant agrees 

 precisely with the foreign, and I have no doubt of their identity. 



9. A. margin&le Willd. : frond bipinnate ; pinnae lanceolate ; pin- 

 nules oblong, obtuse, decurrent, crenate, lower ones almost pinnatifid 

 at base ; sori marginal ; stipe chaffy. Nephrodium marginalc Mich. 



HAB. Rocky woods. Can. to Car. July. 1C. Fern 12 J 8 

 inches high. Stipe chaffy especially near the root. Frond light 

 green, the upper part only fruit-bearing. Involucre orbicular, 

 with a lateral sinus. 



10. A. spinulosum Willd. : frond bipinnate ; pinnules oblong, de- 

 current, with deep cut prickly se"rratures ; involucre orbicular, with a 

 lateral sinus and A. aculeatum Pursh. ? 



HAB. Shady woods. Penn. to Vir. July. If. Pursh. Stipe 

 4ong, scaly at the lower part. Frond broad, with the segments 

 decurrent so as to form a border to the partial rachis. Sori 

 small and rather distinct. Dxibtful as an American plant. 



11. A. dilatatum Willd.: frond bipinnate j pinnules oblong, dis- 

 tinct, incisely pinnatifid ; segments mucroiiate-serrate ; stipe chaff/ 



nd A. intermedium Willd. MM. 



HAB. Shady woods. Can. and N. S. July. II. Fern 12 

 feet high. Stipe long and chaffy. Frond varying j n the divi- 

 sion of the pinna, being sometimes scarcely bipinnate, but 

 sometimes almost tripinnate. Sori numerous, rather large, dis- 

 tinct, brownish when mature. 



