Broadhurst: Struthiopteris in North America 263 



Lomaria ensiformis Liebm. Vid. Selsk. Skr. V. i: 82. 1849. 

 Blechnum ensiforme C. Chr. Ind. Fil. 153. 1905. 



Plants epiphytic. Rhizome creeping, 5-7 cm. long in frag- 

 ments seen, -the scales linear, 5-10 mm. long, maroon to tobacco 

 brown, with a black median line. Sterile fronds 90-100 cm. long; 

 stipes scattered, 20-28 cm. long, channeled on the upper side,* 

 not angulate, marked about halfway down by scarlike undeveloped 

 pinnae, bicolored, the darker side dark chocolate brown, the 

 deciduous basal stipe scalesf smaller than the scales of the rhizome; 

 lamina 40-68 cm. long, 25-35 cm. wide, broadly oblong, abruptly 

 reduced at the base (type A, but with vestigial pinnae as described 

 above), the apex gradually reduced, the terminal pinna 5-8 cm. 

 long, the pinnae more or less opposite, the lower ones distant, 

 sometimes 2-3 cm. apart; pinnae 22-28-jugate, narrowly oblong 

 to linear, straight, not falcate (if curved, only near the apex), 

 horizontal or ascending, 16-18 cm. long, 12-17 mm - wide, t long- 

 acuminate, the base dilated in the upper pinnae, in the lower ones 

 occasionally slightly contracted; margins entire (or barely sub- 

 entire near the apex, not definitely serrate), not at all or very 

 slightly revolute; leaf tissue rigid-herbaceous, without scales; 

 veins not conspicuous, usually sunken on the under side, the vein 

 apices with very slight swellings or depressions, the vein spaces 

 10-13 to 1 cm. Sporophyls 60-70 cm. long; stipes§ 20-28 cm. 

 long, straw-colored or bicolored; lamina 32-45 cm. long, gradually 

 reduced toward the apex, the terminal pinna 5-10 cm. long; pin- 

 nae 20-30-jugate, 10-20 cm. long, 3-4 mm. wide, with a sterile 

 tip 3-6 mm. long, the base contracted (occasionally dilated below 

 the contraction); indusium rather heavy, entire, not becoming 

 lacerate; sporangia dark brown. 



Type locality : Oaxaca, Mexico. 



Distribution: Mexico, Guatemala, Costa Rica, and Panama. 



Specimens included: Guatemala: Baja Verapaz, "Hoch- 



wald bei Purulha," altitude 1,800 m., von Tiirckheim 1693 (Y, N).|| 



* In all of the species included in this paper the rachis and stipe are channeled 

 on the upper (ventral) side; that statement is not, therefore, repeated in the following 

 descriptions. 



t Unless otherwise described in the following species, the basal stipe scales are 

 shorter and more deciduous than the rhizome scales but similar in color and texture. 



% Throughout this paper the measurements of the pinnae are those of the largest 

 lateral ones; the width is measured at the adnate base of the non-petioled pinnae. 



§ Vestigial pinnae, scales, etc., as in the sterile stipes. This likeness will be 

 understood hereafter, unless they are described separately. 



|| N indicates that the specimen cited is in the United States National Her- 

 barium; Y, in the herbarium of the New York Botanical Garden. 



