FERNS— PECOPTERIDE.E—PECOPTERIS. 85 



The sori, although insufficiently clear to show the sporangia, are small, 

 situated near the margin, and a little distant. 



Pecopteris squamosa, which is perhaps intermediate between the groups 

 represented by P. arhorescens or P. cyathea on the one hand and P. vestita 

 on the other, is easily distinguished froni the other plants from Henry 

 County by the size and rigidity of the very slender tapering pinna^ and the 

 small, very narrow, open, crowded, thick pinnules, in which the nervils are 

 usually totally obscured. 



Localities. — Pitcher's coal mine, U. S. Nat. Mus., 5816-5818; Henry 

 County, Missouri, U. S. Nat. Mus., 5600. 



Pecopteris pseudo vestita u. sp. 

 PI. XXyjII, Figs. 1, 2, 2a ; PI. XXIX, PL XXX, PI. XXXI, Figs. 1, 2, 3 ? ; PI. XXXII, 



Figs. 1, 2. 

 1879. Alethopteris ambigiia Lesquereiix, Coal Flora, Atlas, p. T), pi. xsxi, figs. 2, 3 (-L"!); 



text, vol. i (1880), p. 182 (pars). 

 1879. Pecopteris clintoni Lesquereiix, Coal Flora, Atlas, p. S, pi. xlii, figs. .5, 5a-b; 



text, vol. i (1880), p. 251 (pars). 

 1879. Pecopteris vestita Lesquereiix, Coal Flora (Atlas, p. S, pi. xliii, figs. 5, 5«?); 



test, vol. i (1880), p, 252 (pars). 

 1897. Pecopteris n. sp., D. White, Bull. Geol. Soc. Amer., vol. viii, p. 300. 



Frond very large, long, tri- or quadripinnate ; primary (?) pinnae very 

 long, linear-lanceolate, contracted toward the base, the sides nearly parallel 

 in the middle, acute or acuminate at the apex ; rachis Ijroad, rigid, straight, 

 dull, finely but irregularly lineate; pimue of the next order alternate, at a 

 right angle to the rachis below, becoming somewhat oblique above, the 

 higher ones often curving somewhat upward, close, generally slightly over- 

 lapping, especially in the lower part of the frond, oblong-linear or linear- 

 lanceolate, contracted a little at the base, the sides slightly convex in the 

 middle portion, and somewhat abruptly converging near the point to form 

 an acute or acuminate apex, the rachis being broad and rigid; ultimate 

 pinna? alternate, very open, the middle and lower ones at a right angle to 

 the rachis or slightly reflexed, the upper ones frequently nearly at a right 

 angle or but slightly oblique, somewhat irregular, seldom parallel, with a 

 tendency to curve slightly upward, often a little distant, but usually close, 

 and sometimes touching or slightly overlapping, oblong-lanceolate or linear- 

 lanceolate, the sides nearly parallel below and in the middle, rapidly con- 

 verging near the top to an obtuse apex, which consists of an ovate terminal 

 pinnule; ultimate pinnae succeeded near the apex of the superior pinnae by 



