FERN FAMILY 1047 



3. A. cyclosorum Rupr. Rhizome erect or oblique; fronds in a crown, 

 2.8-15 dm. long; blades somewhat softly herbaceous, olive or yellowish green, 

 elliptic-lanceolate, decidedly and rather gradually narrowed toward the base; pin- 

 nae lanceolate or oblong-lanceolate or elliptic-lanceolate, acuminate, pinnatifid 

 toward tip, below pinnate or nearly so; pinnules oblong to lanceolate or ovate- 

 lanceolate, commonly broader than in A. filix-foemina, serrate or incised or deeply 

 pinnatifid, the teeth or lobes often toothed, sometimes doubly so; inSusia very 

 short, usually curved so as to appear circular or irregular, nearly always 

 fringed with long jointed cilia; sporangia without hairs on the pedicel. Woods 

 and open places: Calif, — B.C. — Mont. — N.M.; Alaska and the Old ^Yorld. 

 Undoubtedly will be found more widely distributed in Canada. 



10. ADIANTUM (Tourn.) L. Maiden-hair Fern, 



Venus'-hair Fern. 



Ferns with compound fronds having segments in the form of small leaflets, 

 and slender, usually dark-colored shining stipes. Lobes of the leaflets reflexed, 

 indusiform, bearing the sori on the under side at the ends of the veins. Veins 

 free. 



Stipes forked into two racliises, which bear on upper side pinnae interspersed with single 

 leaflets. 1. A. pedatum. 



Stipes not forked at apex; blades alternately bipinnate or tripinnate. 



Rachiseswavy-flexuose; leaflets very short-stalked. 2. A. modestU7n, 



Rachises strongly divaricate-flexuose; leaflets mostly conspicuously stalked. 



3. A. rimicola, 



1- A. pedatum L. Stipes and rachises dark chestnut-brow^n; fronds 2-5 

 dm. high; principal leaflets dimidiate-triangular-oblong, lobcd on the upper side 

 with unilateral midveins; branches of midveins several times forked. Damp 



woods and in shade near water: Newf. — Ga. — Kans. — (Black Hills) S.D.; Utah; 

 Calif. — Mont. — Alaska; China, Japan, India. 



2. A. modestum Underw. Rhizome creeping, chaffy with light brown scales; 

 stipes and rachises purplish bro'v\Ti to ebeneous; blades 8-29 cm. long and 5-15 

 cm. broad, deltoid-lanceolate to deltoid-ovate, commonly tripinnate; pinnae 

 commonly arched; leaflets 6-15 mm. wide or the terminal wider, nearly as long 

 as wide, truncate, roundish or broadly cuneate at base, equilateral or inequi- 

 lateral, roxmded above, 2-5-lobed, mostly 3-lobed, the incisions shallow, the 

 margin in sterile leaflets, with rare exceptions, evenly and finely serrate-denticu- 

 late, in fertile leaflets similarly toothed between the sori; stalks of pinnules and 

 basal veins commonly greenish white or the stalks light brown; veins repeatedly 

 forked; indusia largely oblong, entire to crenate. Wet places among rocks: Ariz. 

 — s Utah— s Colo.— Tex.; (Black HiUs) S.D. 



3. A. rimicola Slosson, Stipes and rachises dark reddish brown; blades up 

 to 17.5 cm. long and 12 cm. broad, ovate-oblong to ovate-deltoid, mostly broad- 

 est at base; leaflets up to 2 cm. long and 2.5 cm. broad, equilateral or inequi- 

 lateral, narrowly cuneate below, above flabelliform and flaring, at base mostly 

 edged by the first, usually dark bro\\7i, fork of the veins, cleft one-eighth to two- 

 thirds of the way down into 2 or 3 lobes; lobes often shallowly incised, when fer- 

 tile completely recurved between the notches, when sterile sharply serrulate; 

 veins repeatedly forking; indusia transversely elongate, up to 8 mm. long, sub- 

 entire or erose. Cliffs: Utah. L. Son, 



11. PTERIS L. Brake, Bracken. 



Large ferns, with coarse compound fronds and creeping rhizomes. Margins 

 of the frond's divisions reflexed, forming an indusiura. Sporangia borne on a 

 continuous vein-like receptacle connecting the ends of the veins, with an obscure 

 inner inferior indusium attached to the receptacle. Veins pinnate. 



1. P. aquilina L. Stipes up to 9 dm. long; fronds to 12 dm. long, deltoid 

 to ovate-deltoid, subternately decompound, the larger tripinnate below* pin- 

 nules entire, lobed, auricled or pinnatifid, the entire ones mostly oblong or linear, 

 commonly spaced, rarely abruptly dilated at base; costae, midribs, and reflexed 



