IO4 OUR NATIVE FERNS AND THEIR ALLIES. 



shorter; stipes black and polished, as is the lower part of the 

 midrib, especially beneath. Schuylkill River, above Manayunk, 

 Pennsylvania (Scotf) ; Havana, Alabama (Miss Tutwiler) ; 

 Canaan, Connecticut (Adam} ; near Poughkeepsie, New York 

 (Lowri), Jackson County, Illinois (Patterson). 



*** Fronds once pinnate. 

 \ Pinna; f-' long, mostly blunt. 

 \ Rachis chestnut-brown or blackish. 



4. A. platyneuron (L.) Oakes. Stipes 3' 6' long, chest- 

 nut-brown, nearly naked ; fronds 8' 16' long, linear-lanceolate ; 

 pinnae 20 40, lanceolate, subfalcate, or the lower oblong, \' i 

 long, the dilated base auricled on the upper or both sides ; 

 sori often 10 12 on each side. (A. ebeneum Ait., Polypodium 

 platyneuron L.) Florida and Kentucky northward to Canada. 



5. A. parvulum Mart. & Gale. Fronds tufted, erect, 

 rigid, 4' 10' long, narrowly linear-lanceolate ; stipe and rachis 

 black and shining; pinnae numerous, oblong, obtuse, entire or 

 crenulate, auricled on the upper side, nearly sessile ; middle 

 pinnae longest, the lower gradually shorter and deflexed ; sori 

 short, abundant. (A. ebeneum var. minus, Hook., A. resilicns 

 Kunze.) Virginia, South Carolina, and Florida to Arkansas and 

 New Mexico. 



6. A. trichomanes L. Stipes densely tufted, purple- 

 brown, shining ; fronds 3' 8' long, % or more broad, linear ; 

 pinnae 15 30 pairs, nearly opposite, roundish-oblong or oval, 

 the two sides unequal, obliquely wedge-truncate at the base, at- 

 tached by a narrow point, the edge slightly crenate, the mid- 

 vein forking and evanescent; sori 3 6 on each side of the mid- 

 rib. (A. tnelanocaulon Willd.) Eastern United States to the 

 Pacific coast. 



Var. incisum Moore. Fronds larger, often f-' or more 

 broad, pinnae more or less deeply incised. California, Vermont. 



7. A. monanthemum L. Stipes densely tufted, 3' 6' 

 long, chestnut-brown ; fronds 6' 12' long, narrow, with 2040 

 pinnae on each side ; pinnae crenate above, abruptly narrowed 

 at base, often auricled. the lower much reduced; texture sub- 

 coriaceous; veins flabellate ; sori i 2, linear-oblong, parallel 



