ORDER 159. FILICE8. 417 



A large and interesting Order, distinguished for their elegant, plume- 

 like foliage. They are usually a few inches to a few feet high, but some 

 of the Tropical species, as the Cyatheae, are 15 to 25 feet, vieing with the 

 Falms in size and beauty. 



K^T" The stipe is the stalk of the frond, and the rachis its continuation through it. The 

 oimue (orpn.) are the first divisions of a divided frond (often called leaflets). Pinnules 

 (or pnl.) are the first divisions of the pinnae when further divided. Segments (seg.) are 

 the./irco/ divisions, and the partial divisions of the segments are lobes, &c. The sori (fruit- 

 dots) are either naked, or covered with an indusium (see cut). 



I'OLYPODIACE^E. THE TRUE FERXS, with fronds mostly radical, circinate in bud. Fporangia id 



fori, pedicellate, with a vertical, elastic ring, opening transversely. . .(/) 



g CYATHEACE.S. THE TREE FER.NS, with fronds on an erect trunk. Sporangia as in !...() 

 HYMENOPH YLLACE^E. PELLUCID FERWS ; sporangia in a cnp and on a thread. . .(d) 

 SCIII/.KCE/E. Very slender vines or fronds. Sporangia with a ring-crown at apex... (c) 

 i OSMUNDIACEJ2. Fronds stout, radical. Sporangia with no ring, 2-valved. . .(6) 

 I OPHIOGLOSSACE..E. Frond single (in our species), on an erect stem. Sporangia with no ring... (a) 



a Fruit in a spike. Frond entire, reticulate-veined. OPHIOGLOSSCM. 1 



a Fruit in a panicle. Frond divided, fork-veined BOTKYCHICM. 3 



b Fronds pinnate or bipinnate, with straight, forked veins OSMCNDA. 3 



t Frouds palmate! y lobed. Stems climbing, 3 If LYGODIUM. 4 



Fronds linear-filiform, undivided, a few inches high SCHIZ.SA. 5 



e Fronds 3-parted, middle division sterile, the lateral paniculate A XKI MI A. 6 



d Fronds pellucid or opaque. Sporangia with a transverse ring TRICHOMANES. 7 



e Fruit-dots in little round cups. Trunk and leaves smooth OTATBEA. S 



Fruit-dots becoming entirely naked. Fronds prickly or hairy ALSOPHILJL i 



* Fruit-dots enclosed in the rellexert tip of the lobe, with two valves KALA.NTIU.M. 22 



/ Sporangia scattered singly all over the surface (not in sori), naked. ..(//) 

 I Sporangia collected in dots (sori) growing from the veins... (A) 



q Fronds simple or pinnate. Pinna; on short petiolules ACROSTICHUM. 10 



g Fronds forked at the summit, entire below, the sterile different PLATYCERIUH. 11 



A Sori (fruit-dots) naked, having no covering of any kind. . .(/r) 



h Sori involved (at first) in the rolled segments of the panicled fertile frond... (m) 



h Sori not involved, but iuvested with special coverings (called imlitfia) . . .(n) 



k Fronds smooth or scaly, never powdery. Sori distinct, roundish POLYPODIUM. 12 



k Fronds covered with powder on the back. Sori in many dorsal lines GYMNOGRAMM A. 13 



k Fronds powdery or scaly on the back (bipinnate). Sori in a marginal line NOTHOL^EWA. 14 



k Fronds linear, simple. Sori in a continuous line on the split margin. Fla VITTARIA lineata 



m Fertile frond bipinnate, segments berry-like. Veins reticulated ONOCLEA. 16 



HI Fertile frond pinnate, pinnae moniliform. Veins forking STRUTHIOPTERIS. 16 



m Fertile fronds bipinnate, segments oblong, soon opening ALLOSORUS. 17 



* Sori marginal, induxia only the reilexed altered margin of the frond. ..(o) 



* Sori marginal, indusium double a scale combined with the margin. . . <;<) 

 n Sori dorsal, oblong or linear, indusium attached to the side of a vein. ..(q) 



H Sori dorsal, round or roundish, indusium on the back or the tip of a vein...(.c) 



o Fronds of 2 kinds, the fertile contracted. Sori continuous to apex LOMARIA. 18 



o Fronds all similar, smooth. Indusia continuous all around. Stipe green or brown. .PTERIS. 19 



o Fronds woolly, Ac. Sori separate or continuous. Stipe brown, hairy CHEILANTHKS. 20 



o Fronds smooth Sciri separate. Stipe black and polished ADIANTUM. 21 



f Indusium a 2-lipped cup at the edge of the segments DICKSOMA. 22 



p Induium an entire cup or goblet at the edge of the segments DAVALLIA 28 



q Sxiri parallel to the mid-vein, the indusia opening toward it. ..(r) 

 q Sori oblique to the mid- vein, borne laterally on the veinlets. . .() 



r Sori linear, nearly continuous, in 2 rows, sunk in the frond .' WOODWARDIA 24 



r Sori oblong, remote, in two rows and superficial. Stipes black DOODIA 25 



r Sori linear, in 1 double row, the whole length of the segment BLECHNUM. 28 



r Sori oblong, in 1 short double central row. Frond finely cleft ONYCHIUM. 27 



t Indusia single, regularly arranged, in 2 rows ASPLKNIUM. 28 



Indusia single, scattered irregularly. Frond simple or lobed CAMPTOSORUS. 28 



Indusia double, regularly arranged. Frond simple. Scot.OPKunRiBM. 30 



