16 OUR NATIVE FERNS AND THEIR ALLIES. 



oles 2-forked, each fork bearing a round-cordate palmately 4 — 7- 

 lobed pinnule ; fertile pinnules above, contracted, several times 

 forked, forming a terminal panicle ; surfaces naked ; texture 

 thinly herbaceous. (Hydroglossum palmatum Willd.) Mas- 

 sachusetts and New York to Kentucky and Florida. 



II. ORNITHOPTERIS Bernh. 



Sporangia ovate, sessile, placed in two rows on the back of 

 the very narrow branchlets of the two long-stalked, panicled, 

 lower branches of a pinnately divided frond, the fertile branches 

 in a few species entirely distinct from the sterile frond. Veins 

 free. Name from Gr. opvii, bird, and itrepii, fern. A genus 

 mostly of tropical America containing about 35 species. 



1. O. adiantifolia (L.) Bernh. Rootstock creeping ; stipes 

 i\° long, firm, naked ; fronds sparingly pubescent, the two lower 

 branches elongate, pinnately decompound, fertile; sterile por- 

 tion deltoid-ovate, bi — tripinnate ; ultimate segments obovate 

 or cuneate, entire or lobed, striate above with numerous flabellate 

 veins. (Anemia adiantifolia Swz.) Florida. 



2. O. Mexicana (Kl.) Underw. Rootstock creeping, cov- 

 ered with narrow blackish chaff; stipes slender, scattered, 6'— 12' 

 long ; the two lower branches of the frond fertile, long-stalked, 

 glandular, bipinnate with densely clustered fructification ; the 

 rest of the frond like the sterile ones, deltoid-ovate, simply pin- 

 nate ; pini.ae about six pairs and a rather large terminal one, 

 short-stalked, ovate-lanceolate, subcoriaceous, smooth and some- 

 what glossy ; midrib distinct, veins free, oblique, parallel, closely 

 placed. {Anemia Mexicana Klotzsch.) Western Texas. 



III. SCHIZ^EA Sm. Curly-grass. 



Sporangia large, ovoid, striate rayed at the apex, naked, ver- 

 tically sessile in a double row along the single vein of the nar- 

 row divisions of the fertile appendages to the slender and sim- 

 ply linear, fan-shaped, or dichotomously many-cleft fronds. 

 Name from Gr. (Txi'^^iv, to split, alluding to the forked sterile 

 fronds of foreign species. Includes 16 species. 



§ EUSCHIZiEA. 



I. S. pusilla Pursh. Sterile fronds linear, very slender, 

 flattened and tortuous ; fertile ones equally slender, 3' — 4' high. 



