8 



A SYNOPSIS OF THE PLANT KINGDOM 



Sub-class II. Leplosporangialse. Sporangial wall 

 one cell in thickness 



Order 3. FILICALES 



3. Hymenophyllacese (from the genus Hymeno- 

 phyllum, signifying membrane-leaved). FILMY-FERN 

 FAMILY. Kg. 2. Very delicate ferns, small or minute in 

 size, frequently epiphytic: leaves entire, 1-3-pinnate. or 

 dichotomously divided, rarely thalloid or orbicular, 

 reduced in thickness to a single layer of cells between 

 the veins, and thus often resembling the leaves of 

 mosses; stomates absent; ultimate or all veins dichoto- 

 mous: sori marginal, raised on a slender columnar pro- 



2. HYMENOPHYLLACE-E: 1. Hymenophyllum, section of sorus. 

 CYATHEACE.E: 2. Alspphila, sporangium. POLYPODIACE/E: 3. Aa- 

 pidium, o, pinnule with sori; 6, section of sorus. 4. Adiantum, 

 prothallium with young fern plant. 5. Polypodium, a, archego- 

 nium; 6, antheritiium; c, sperm. 6. Peranema, sporangium. GLEICH- 

 ENIACE&: 7. Gleichenia, sporangium. 



jection of the veinlet: indusium cup-shaped: sporan- 

 gium thin-walled; dehiscence vertical or oblique ; 

 annulus complete, horizontal: prothallium thalloid or 

 filamentous, often much branched. 



There are 2 genera and about 200 species growing 

 upon rocks and trees in the damp, shady forests of the 

 tropics, and in New Zealand. One species reaches 

 central Europe and another reaches Kentucky. The 

 family is readily distinguished by the delicate leaf, 

 pedicelled sorus and equatorial annulus. 



The Hymenophyllacese require a warm and very 

 humid atmosphere, and, therefore, most species are 

 difficult to cultivate. 



Several species of Hymenophyllum and Trichomanes 

 are in cultivation in America. 



4. Cyatheaceae (from the genus Cyathea, signifying 

 cup+contain, in reference to the cup-shaped indusium). 

 CYATHEA FAMILY. Fig. 2. Usually tree ferns with 

 large, much-compounded, circinate leaves: sori globu- 

 lar, borne on the under side of the leaf: veins forking: 

 indusium usually present, bi-valvular, cupular or uni- 

 lateral: sporangia thin-walled, sessile or short-pedi- 

 celled, obovoid ; annulus complete at the pedicel, 

 oblique, dehiscence transverse: prothallium ordinary, 

 green. 



This family has 7 genera and about 300 species, of 

 which 115 belong to Cyathea, 112 to Alsophila, and 44 

 to Hemitelia. They are distributed in the tropics of 



both hemispheres. The Cyatheacese is closely related 

 to the Polypodiaceas from which it differs only in the 

 slightly oblique annulus which passes just at one side 

 of the insertion of the pedicel, and is therefore unin- 

 terrupted at that point. 



The dense, woolly covering of the stem of many species 

 is sometimes collected for stuffing pillows. The starchy 

 pith of some New Zealand Cyatheaceae was formerly 

 used for food. In India, an intoxicating drink is pre- 

 pared from the pith. Several species are important 

 greenhouse ferns. 



Five genera at least are listed in the American 

 trade: Alsophila, Cibotium (Scythian Lamb), Cyathea, 

 Dicksonia, Hemitelia. 



5. Polypodiaceas (from the genus Polypodium, signi- 

 fying many feet, in allusion to the branched rootstock 

 of some species). POLYPODY FAMILY. Fig. 2. Ferns of 

 very diverse habit, rarely arborescent: leaves of nor- 

 mal texture, entire or pinnatifidor multisect, circinate; 

 veins forking: sori mostly on the under side of the leaf; 

 indusium peltate, fringed, capillary, cupular, elongated, 

 unilateral or wanting: sporangia thin- walled, long- or 

 short-stalked; annulus vertical, interrupted by the 

 pedicel; dehiscence transverse: prothallium thalloid, 

 green, growing upon the surface of the soil, mostly 

 bisexual. 



Polypodiaceas has more than 100 genera and about 

 4,000 species of wide distribution; especially abundant 

 in humid regions and in forests. The largest genera are: 

 Dryopteris (or Aspidium), 450 species; Polypodium, 

 500 sp.; Asplenium, 150-200 sp.; Elaphoglossum, 80- 

 100 sp.; Adiantum, 80 sp.; and Pteris, Blechnum, 

 Polystichum and Aspidium about 50-70 species each. 

 The family is most closely related to the Cyatheacese. 

 The presence of sori, the thin-walled sporangium with 

 vertical interrupted annulus and transverse dehiscence 

 are distinctive. This comprises the larger number of 

 ferns, and is often called the Fern Family. 



Some of the most striking variants are the walking- 

 leaf fern with undivided lanceolate leaves which take 

 root at the apex and repeat the process several times, 

 all the plantlets remaining for a time connected; the 

 hart's -tongue fern with broadly lanceolate - oblong, 

 entire frond; the epiphytic staghorn fern with erect, 

 forked, fertile fronds and orbicular entire, sterile fronds 

 closely imbricated over the short stem and support. In 

 many species the fertile and sterile fronds are dimorphic. 

 The stems of some species are slender and climbing; 

 others long, slender and creeping; some are very stout 

 and erect (tree ferns) . 



The ferns are of little economic importance except 

 as ornamental plants. The starchy rootstocks of some 

 species are eaten locally, as are also the young shoots. 

 The rootstock of Dryopteris (Aspidium) Filix-mas is a 

 reputed vermifuge. 



About 60 species are in cultivation in America. 

 Among these are: Adiantum (Maidenhair Fern); 

 Aspidium (Shield F.); Asplenium (Spleenwort) ; Camp- 

 tosorus (Walking-leaf F.); Dennstcedtia (Dicksonia) 

 (Fragrant F.); Onoclea (Sensitive F., Ostrich F.); 

 Peltea (Cliff Brake); Phegopteris (Beech F.); Platyce- 

 rium (Staghorn F.); Polypodium (Polypody F.); 

 Polystichum (Holly F., Christmas F.) ; Pteris (Common 

 Brake); Scolopendrium (Hart's-tongue F.). 

 6. Ceratopteridaceae (Parkeriaceae) (from the genus 

 Ceratopteris, meaning horn-fern). CERATOPTERIS 

 FAMILY. Aquatic ferns rooting in the mud: leaves of 

 two sorts, the ones less divided with broader segments 

 and veins more or less anastomosing; the more aerial 

 fertile ones much divided, with narrow segments, and 

 revolute margins which later almost completely inclose 

 the scattered sporangia: indusium wanting: sporangia 

 globular, thin-walled with a very diverse broad nearly 

 complete or nearly wanting annulus; rarely the annulus 

 wanting; dehiscence transverse: prothallia unisexual, 

 thalloid; antheridia not superficial. 



