30. PELL^A, §§ ALLOSORUS. 149 



loth surf aces nnV&di ; veins beneath prominent, the lateral ones forked ; sori copions, 

 confluent, marginal ; invol. liroarl, memhranaceous, frinj^ed. — Clieil., Hk. Sp. 2. 

 p. 112. — /3, scrrat'if'tlia {HIc. 2tidOen(. t. 72) ; pinnules distinctly toothed. Pteri8 

 fallax, Mart. & Galeotti. 



Hab. Mexico and Guatemala. 



21. P. (Alio.) ornithoptis, Hk. ; st. tufted, 3-G in. 1., rigid, erect, polished, dark 

 chesnut-brown, nuked ; fr. 4-0 in. 1., 2-3 in. br., deltoid, bipinnatifid ; innnoi 

 rigid, spreading, 1-1^ in. 1., j-§ in. br., with numerous distantly-placed sessile 

 piunpe on each side, which are cut to the base into three linear mucronate scgm., 

 of wliich the central one is the largest, but is not more than 1^-2 lin. 1. ; rachis 

 polished like the sti[)e ; texture coriaceous ; both surfaces naked, very pale 

 glaucous-green ; invol. broad, coriaceous, crenate, rolled permanently over the 

 soii.—BLSp. 2. p. Ui. t. 110. A. 



Hab. California. — The pinnules here are clawed like the pinnae of P. ternifolia. 

 ** Frond at least triinnnatifid. Sp. 22-32. 



22. P. (Alio.) nitichila, Baker ; st. densely tufted, slender, dark chesnut-brown, 

 polished, 8-Gin. I., filJrillose below;//-. 3-4 in.l., 1-Hin. br., bi-tripinnatifid ;jt>2V»i(» 

 opposite, the lower ones deltoid, cut down to the rachis into a iew j^iynl., the upper 

 ones linear-oblong, entire, the lower ones again pinnatifid ; rachis and both sur- 

 faces naked ; sori copious, confluent ; invol. broad, membranous, toothed. — Cheil., 

 BLSp. 2. p. 118. Ic. PI. 10. t. 912. Allosorus, Pm-^. 



Hab. Himalayas, ascending to 6,000 ft. 



23. P. (Alio.) clensa, Hk. ; sf.^ tufted, 4-0 in. 1., slender but wiry, polished, 

 chesnut-brown, naked; /;•. 2-3 in.l., 1-H in. br., oblong-deltoid, tripinnate ; 

 pinnce and jnnnl. crowded, deltoid or lanceolate ; segm. numerous, linear, with 

 enrolled edges, sessile or shortly stalked, sharp-pointed or mucronate, the terminal 

 ones the largest, sometimes ^ in. 1. ; texture coriaceous ; rachis and both surfaces 

 naked ; invol. broad, rigid, rolled permanently over the sori. — Hk, Sp. 2. p. 150, 

 t. 125. B. Onychium, Brack. 



Hab. Oregon, Washington territory, and California. 



24. P. (Alio.) rohusta, Hk. ; st. 1-2 in. 1., erect, wiry, bright-brown, naked, 

 polished ; .fr. 2-3 in. 1., 1 in. or less br., oblong, obtuse, tripinnatifid ; jnnnce 

 ^-| in. 1., deltoid, cut down to the rachis into several pinnl. on each side, with a 

 few thick linear-oblong simple or forked segm. not more than 1^ lin. 1., \ lin. br.; 

 texture subcoriaceous ; rachis and both surfaces light-green, naked ; sori in a 

 continuous line along both edges ; invol. similar in sutjstance to the frond, and 

 rolled over the fruit till full maturity. — Hk. Sp. 2. p. 147. 



Hab. Namaqua Land, S. Africa. — This and P. «?e)!sa are very like Cryptogramme cnspa 

 in size and habit, but the barren and fertile fronds are similar, the segments smaller 

 and more crowded, and the involucre thicker in texture. 



25. P. (Alio.) Boivini, Hk. ; st. 4-8 in. 1., strong, erect, naked, dark-brown, 

 polished ; fr. 0-9 in. 1., 4-0 in. br., subdeltoid, hi- or tripinnate ; pinnai erecto- 

 patent or spreading, growing gradually smaller upwards, the lowest broadly 

 lanceolate, simply pinnate, or occasionally bipinnate ; ult. segm. ovate, bluntish 

 or acute, |-1 in. 1., |^-| in. br., shortly stalked, cordate or rounded at the base ; 

 texture coriaceous ; rachis tomentose ; both surfaces naked ; veins sunk in the 

 frond ; sori in a continuous line all round the segments ; invol. membranous, 

 nearly half a line broad. — Hk. Sp. 2. p. 147. t. 118. A. 



