FERN FAMILY. 363 



VL OPHIOGLOSSACEiE, the ADDER'S-TONGUE FAM- 

 ILY: mostly rather small ferns, with sessile, globular, coriaceous 

 opaque and smooth spore-cases, opening transversely into 2 valves, 

 and wholly destitute of a ring. Fronds not rolled up in the bud, 

 as they are in all the foregoing, rising from a very short rootstock 

 or corm, with fleshy roots. 



29. BOTRYCHIUM. Spore-cases in pinnate or compound spikes, distinct. Sterile 



part of the frond compound ; veins free. 



30. OPHIOGLOSSUM. Spore-cases cohering in a simple spike. Sterile part of 



frond simple in our species ; the veins reticulated. 



1. ACROSTICHUM § CHRYSODIUM. (From Greek words meaning 



a row at the top, the application not evident.) All tropical. 



A. atireum. A large evergreen Fern, along the coast of South Florida ; 

 the fronds simply pinnate, coriaceous; pinnaj 4' -6' long, l'-2' wide, elliptical 

 or oblong-linear. 



2. PLATYCERIUM, STAG-HORN FERN. (Name from the Greek, 

 meaning broad horns.) Natives of Atrica, Australia, &c. : cult, in conserva- 

 tories. 



P. alciedrne. Sterile fronds sessile, rather thin, flat and rounded, over- 

 lapping each other; fertile ones erect, 1° high, whitish and minutely downy 

 beneath, 2-3 times forked, with divisions about 1' wide, the topmost ones 

 fruitful. 



3. POLYPODIITM, POLYPODY. (Name in Greek means many-footed, 

 referring to the branching rootstock.) An immense genus, found in all parts 

 of the world. 



§1. PoLYPODiUM proper. Veins free : the following all native. 

 P. VUlgare, Common Polypody. Rocky places N., small, simply pin- 

 natifid, evergreen, smooth both sides, 4' - 10' high, 1'- 3' wide, the numerous 

 divisions oblong-linear ; fruit-dots rather large. 



P. incanum. Shady places S., often on trees ; much like the last, but 

 much smaller, and beneath grayish and scurfy with peltate scales ; fruit-dota 

 rather small. 



§ 2. CAMPYLONEtTRON. Veins parallel, pinnate from the midrib, connected by 

 numerous transverse angularly arched veinlets, with short fruit-bearing vein- 

 lets proceeding from the angles. 



P. Phyllitidis, Harts-tongue, of Tropical America; frond simple, 

 linear-lanceolate, l°-lp long, l'-2' wide, thinly chartaceous, smooth and 

 shining ; fruit-dots in 2 rows between the veins. 



§ 3. Nipii6bolus. Veins much as in the preceding, but very obscure and closely 

 reticulated. Fronds simple, of a thickish texture, covered on both sides with 

 a close stdlate down. 



P. Lingua. Cult, from Japan : fronds 4' - 8' long, ovate-oblong or lanceo- 

 late, entire, at length nearly smooth above ; fruit-dots exceedingly numerous, 

 closely arranged in many rows. 



§4. Phleb6dium. Veins reticulated, with free veinlets included in the larger 

 meshes. Fruit-dots in 1 -3 roics betn-een the vndrib and margin, commonly 

 placed each one on the converging ends of a pair of veinlets. 

 P. atireum. A large showy Fern of Florida, and cult, from West Indies ; 

 fronds on a stout stalk, broadly ovate in outline, smooth, pale green above, 

 glaucous beneath, pinnately parted into 5-9 or more oblong-linear or lanceo- 

 late spreading divisions. 



