ACROGENS. 15 



2. Fronds scattered, deciduous. 



L. noveboracensis, fronds lanceolate, lO'-l 8' long, hairy . L. Thel^p- 

 teris, similar, but smoother. Both In bogs, TJ. S. 



13. Nephrodium. — Indusium of 11; but veins anastomosing; and 

 fronds in a crown, evergreen. N. m6Ue, fronds pinnate, ovate-oblong, 

 l°-2° high, whole plant downy. Tropics. N. patens, similar, but 

 less hairy. Shady grounds, Florida, W. 13. Camptosorus, sori 

 curved; veins reticulate. C. rhizoph^Uus , Walking P. ; frond k'-\2' 

 long, cordate at base, tapering to a long point, rooting at apex. Damp 

 rocks, rare, TJ. S. 14. Athyrium, sori lunate; veins free. A. F'llix- 

 foemma. Lady F. ; fronds lanceolate, 2-3-pinnate, delicate, 2°-6° 

 high, in a crown. Moist woods ; cosmopolitan ; common throughout 

 Tennessee. 15. Scolopendrium, Hart's-Tokque, Centipede F. 

 Sori linear, double ; veins free. S. vulgare, frond simple, oblong- 

 lanceolate, 6'-18' long. Gt. Brit, Can., IJ. S., north. Fig. 35. 

 Cultivated forms are curled, furcate, etc. 



16. Asplenium. — Sori linear, usually single, sometimes solitary. 

 Veins free. 2 Sections : 



1. Sori few. 



A. bulbiferum, fronds lanceolate, l°-3° long, 2-3-pinnate, bulbif- 

 erous above. New Z.- A. myrioph'gllum, fronds l°-2° high, 2-3-pin- 

 nate, translucent. Limestone caves, Florida. A. Belangeri, fronds 

 l°-2° high, lanceolate, 2-pinnate, coriaceous. Malacca, Java. A. tke- 

 lypteroides, fronds l°-3° high, broad lanceolate, pinnate, pinnae deeply 

 pinnatifld. Common in woods. A. furcdtum, fronds 8'-15' high, 

 ovate-lanceolate, pinnate, pinnae cut almost to midrib. Trop. Am., S. 

 Af. A. Ruta-murdria , Wall-Kue F., fronds 2-3-pinnate, \'-^' long, 

 ovate, thick, dentate at top. Cliffs, Vermont, S. and W. 



2. Sori numerous, (except in A. Trichomanes). 



A. anc/ustif oHum, fronds pinnate, long-lanceolate, l°-3° high. 

 Woods, tl. S. A. jlabellifblium, fronds pinnate, i'-lb' high, pinnae 

 flabelliform, crenate. Australia. A. ebeneum, fronds pinnate, linear- 

 lanceolate, 8'-15' long, on a dark shining stalk; pinnae linear-oblong, 

 finely serrate, auricled at base. Common, TJ. S. A. Trichomanes, fronds 

 pinnate linear, 4'-8' long, stalk and rachis black, shining. Tufted, 

 in crevices of rocks. Common. A. pinnatifidum, fronds pinnatifid 

 below, tapering to a long, entire point ; 3'-6' long. S. Penn. , W. and S. 

 A. Nidus, Bird's-Nest F. ; fronds broad, lanceolate, simple, entire, 

 2°-4° long, in a crown around an erect rhizome. E. Ind. 17. Doodia. 

 Sori .slightly lunate; veins reticulate. Fronds small. D. dspera,- 

 fronds 9'-15' long, broad-lanceolate, deeply pinnatifld ; stalk black, 

 rough. D. cauddta, frond 9'-] 5' long, linear-lanceolate, pinnate; 

 lower pinnae triangular, distant; stalls black. Both from Australia, 

 New Z. 18. Woodwardia, Chain F. Sori linear, immersed, form- 

 ing chains ; veins reticulate. W. angustifblia, frond lanceolate, 6'-10' 

 long, pinnatifid ; fertile segments narrow. Swamps, N. and S. Vf. 

 virginica, fronds 2° high, ovate, pinnate, pinnae deeply pinnatifid. 

 Fertile and sterile fronds alike. Habitat of last. 19. PlatyI6ma 

 (Pellafea), Cliff Bkake. Small. Sori marginal, veins free. P. 

 atropurpitrea, frond 6'-12' long, lanceolate, 2-pinnate ; tufted. On 



