ORDER 160. FILICES. 819 



S. Genndnica "Willd. A Fern of noble port, in low woods and swamps, K". 

 States and Can., common. The sterile fronds are often 5 or 6f high, commonly 

 about of, numerous, in a circular clump. Stipes smooth, channeled. Pinnae nu- 

 merous, crowded, long, linear, each with numerous oblong segments of which the 

 lowest is longer and acute, all more or less connected at base. Fertile fronds few 

 in the midst of the sterile, much smaller, the pinnte subterete, 1 to 2' long, crowded. 

 Sori about 5 in each segment, on the raised ends of as many veinlets. Aug. 



9. PTE'RIS, L. BRAKE. ROCK BRAKE. (Gr. -rrrepdv, a wing.) 

 Sori borne on the ends of the veins forming a marginal line, covered 

 Avith the membranous, reflected edge of the frond. Fronds ouce to 

 thrice pinnate or decompound. 



Frond pednte, or tern.-.te and bipinnatifld. Sori in a continuous line Nos. 1, C 



Frond partly bipinnato. Sori at first distinct but soon continuous Nos. 3, 4 



1 P. aquilina L. Coiniox BRAKE. Frond 3-parted ; branches bipinnate ; lfts. 

 oblong-lanceolate, lower ones pinnatifid, upper ones entire; segments oblong, 

 obtuse. Abundant in woods, pastures and waste grounds. Fern 2 5f in height, 

 upon a smooth, dark purple, erect stipe. Frond broad-triangular in outline, con- 

 sisting of 3 primary divisions, which are again subdivided into obtusely pointed, 

 sessile leaflets. These are entire above, becoming gradually indented towards 

 the base of each subdivision. Sori covered by the folding back of the very mar- 

 gins of the segments. 



i3. CAUDATA. Segm. of the pinna3 linear oblong, the terminal one much elon- 

 gated. The common Southern form. 



2 P. pedata Willd. Frond ternately parted, the lateral divisions 2-parted, all 

 pinuatifid ; segm. linear-lanceolate, acute, the lowest segment of the terminal 

 division pinnatifid; terminal division long-cuneiform at base, recesses acute. On 

 rocks, Va. (Pursii). Fern about 6' high. 



3 P. atropurpurea L. ROCK BRAKE. Frond pinnate; rachis hairy; lower 

 l.'ts. ternute or pinnate, segments lance-oblong, obtuse, obliquely truncate or vSub- 

 eordate at the petiolate base. Fern 6 10' high, growing on rocks, Can., Wis.. 

 Yt. to. Term. ! and Ala. ! Frond twice as long as wide, of a grayish hue, the two 

 lower divisions consisting of 1 3 pairs of leaflets with a, long, terminal segment. 

 All the segments distinct, with margins conspicuously revolute. Some of the 

 larger have 1 or 2 auricles at base. Stipe and rachis dark purple, with dense, 

 paleaceous hairs at base. June Aug. (AUosorus, Gr. P. Alabamensis Buckley, 

 \vheu the upper segments are generally auricled.) 



4 P. gracilis Michx. Frond slender, lanceolate, sterile ones pinnate, leaflets 

 pinnatifld, segments broad-ovate, obtuse ; fertile bipinnate, leaflets linear-oblong, 

 crenate. A delicate species, growing on rocks. Fern 4 6' high, smooth and 

 shining throughout. Both this and No. 3 are homogeneous in habit with the 

 others. Their separation to a new genus is an over-refinement. ( AUosorus, Presl.) . 



10. CHEILANTHES, Swartz. LIP FERX. (Gr. ^eUo?, a lip, avdos ; 

 from the form of the indusia.) Sori roundish, distinct, situated at the 

 margin or apex of the segments ; indusia distinct, formed from the 

 reflected margin and opening inwards. Segments of the frond with the 

 midvein central. 



1 C. vestita Swartz. Stipe and rachis hairy; frond bipinnate, oblong-ovate in 

 outline, hairy on both sides; leaflets alternate; segments oblong, alternate, ses- 

 sile, distinct, crenately pinnatifld, the ultimate segment very entire; sori distinct, 

 their indusia unchanged. Rocky banks, Penn. to Mo. and South. Stipe slender, 

 rigid, 2 3' long, dark brown. Fronds 3 6' by 1 2'. Leaflets lance-ovate in 

 outline, 6 12" long. A small and delicate, hairy Fern. JX 



2 C. tomentosa Link. Stipe stout, and with the rachis and frond clothed with 

 a dense ferruginous wool ; frond tripinnate, ultimate segments rounded or oblong, 

 obtuse (upper ones confluent), fruit-bearing around the whole margin. N. Car. 

 (Curtis) and Term. Fern If to 18' high, much larger and more hairy than tLe 

 preceding. Both species are less hairy on the upper than the under surface. 



