30. PELL^EA, ALLOSORUS. 149 



both surfaces naked ; veins beneath prominent, the lateral ones forked ; sori copious, 

 confluent, marginal ; invol. broad, membranaceous, fringed. Cheil., Hk. Sp. 2. 

 p. 112. J3, serratifolia (Hk. 2nd Cent. t. 72) ; pinnules distinctly toothed. Pteris 

 fallax, Mart. $ Galeotti. 



Hab. Mexico and Guatemala. 



21. P. (Allo.) ornithopus, Hk. ; st. tufted, 3-6 in. 1., rigid, erect, polished, dark 

 chesnut -brown, naked ; fr. 4-6 in. 1., 2-3 in. br., deltoid, bipinnatifid ; pinnae 

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

 pinnae on each side, which are cut to the base into three linear mucronate segm. 9 

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

 polished like the stipe ; texture coriaceous ; both surfaces naked, very pale 

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

 sori. Hk. Sp. 2. p. 144. t. 116. A. 



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

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



22. P. (Allo.) nitidula, Baker; st. densely tufted, slender, dark ehesnut-brown, 

 polished, 3-6 in. 1., fibrillose below ;fr. 3-4 in. 1., 1-1^ in. br., bi-tripinnatifid ^ pinnae 

 opposite, the lower ones deltoid, cut down to the rachis into a few pinnl., the upper 

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

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

 Hk. Sp. 2. p. 113. Ic. PL 10. t. 912. Allosorus, Presl. 



Hab. Himalayas, ascending to 6,000 ft. 



23. P. (Allo.) densa, Ilk. ; st. tufted, 4-6 in. 1., slender but wiry, polished, 

 chesnut-brown, naked ; fr. 2-3 in. 1., 1-1^ in. br., oblong-deltoid, tripinnate ; 

 pinna? and pinnl. 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. (Allo.) robusta, 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 ; pinna? 

 $-f 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 \\ lin. 1., \ lin. br. ; 

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

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

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



Hab. Namaqua Land, S. Africa. This and P. densa are very like Cryptogram/me crispa 

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

 polished ; fr. 6-9 in. 1., 4-6 in br., subdeltoid, bi- or tripinnate ; pinnce erecto- 

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

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

 or acute, f-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. 1. 118. A. 



