80 Vol. XLIII., Art. 1.— K. Yen do : 



in width at the broadest part, membranaceous, richly transversely 

 corrugated, cryptostomata wanting, margin finely crispated, splitting 

 in the older parts transversely to the midrib ; base of blade gently 

 tapering or acute when young, roundish or even cordate when old, 

 tip of blade narrowed above, pinnately split and usually worn 

 away. Stipe 5-12 cm. in length, cylindrical below in well develop- 

 ed and matured specimens, 4-6 mm. in diameter, terete and more 

 or less broadened above, narrowed below the transition point, 

 lower half of the length naked, up'per terete part bearing the 

 sporophylls, but in the yonnger individuals subcompressed or an- 

 cipitous till almost to the base, and bearing sporophylls from near 

 the base. Midrib complanated, C-10 mm. broad, elevated above 

 the blade equally on both surfaces with round edges, continuous 

 with the stipe below. Sporophylls holosoric, 30-40 in number, 

 pinnately arranged on both margins of the terete part of the stipe, 

 a few lowermost ones more or less apart, but the middle and 

 upper ones close together, with the bases of the petioles fused 

 into a continuous narrow wing on each margin of the stipe, lan- 

 ceolate or linear- cuneate, 20-30 cm. long, 3.0-4.5 cm. wide in the 

 broadest part ; base of sporophyll acute, often obtuse, very frequent- 

 ly oblique, ending in a cylindrical petiole ; tip obtuse with rounded 

 apex, or often round. Sorus in a continuous patch on both sur- 

 faces of each sporophyll, occupying generally the entire area of 

 the surface except a narrow border along the margin, but frequent- 

 ly leaving an upper part sterile and membranaceous. 



Remarhx on the limit of variation. The present species attracts 

 the attention of the collector by its finely corrugated and very 

 long blade. This character, however, is often not remarkable in 

 some individuals, especially in the lower half of the length. In a 

 herbarium specimen, when the upper portion has been cut off. 



