STANDLEY — TKEES AND SHRUBS OF MEXICO. 43 



Mountain forests near Lobani, District of Cliinantla, Oaxaca, at 900 to 1,050 

 meters ; known only from the type collection. 



Caudex about 30 cm. high; blades ovate-lanceolate, about 75 cm. long; 

 pinnae narrowly oblong-lanceolate, 12 to 15 cm. long, 2.5 to 3 cm. broad, the 

 upper ones adnate and confluent, those below semiadnate, constricted, narrowly 

 long-decurrent. 



4. Hemitelia mexicana Liebm. Dansk. Vid. Selsk. Skrivt. V. 1: 287. 1849. 

 Hemistegia mexicana Fourn. Mex. PI. Crypt. 135. 1872, 



Oaxaca, in mountain forests near Cacola, District of Chinantla, at 750 to 900 

 meters altitude ; known only from the original collection. 



Caudex about 30 em. high ; blades broadly lanceolate, 1.5 to 1.8 meters long ; 

 pinnae linear, about 30 cm. long; main veins 50 pairs, spreading, 4 to 7 mm. 

 apart. 



5. Hemitelia lucida (Fee) Maxon, Contr. U. S. Nat. Herb. 16: 39. 1912. 

 Hemistegia lucida Fee, Gen. Fil. 351. 1852. 



District of Chinantla, Oaxaca, at 2,000 meters altitude; known only from 

 the type collection. 



Blades ovate-oblong, 2 meters long or less ; pinnae numerous, linear-lanceolate, 

 up to 45 cm. long ; main crenations or lobes 28 to 34 pairs. 



3. ALSOPHILA R. Br. Prodr. Fl. Nov. HoU. 158. 1810. 



Similar to Cijathea, but having the indusia wholly lacking or, in a few species, 

 represented by a very minute, concealed, vestigial, basal scale ; receptacles often 

 copiously long-paraphysate. 



Two subgenera, Lophosoria and AmpMdesmium, are unique in their silky 

 capillary scales, which are similar to those of Clhotium and Dicksonia. They 

 differ notably from typical Alsophila in other morphological characters also 

 and possibly should be regarded as distinct genera. AmpMdesmium is not 

 known to occur in Mexico, though it occupies a wide range southward. Lopho- 

 soria is represented by the variable and widely distributed A. quadriplnnata, 

 the first-mentioned species below. 



Blades waxy-pruinose beneath, the rachises, costae, and veins lanate with lax, 

 tortuous, pale rusty, septate hairs ; sori with low hemispheric receptacles ; 

 caudex and stipe bases densely clothed with silky capillary scales 1 cell 



broad 1. A. quadripinnata. 



Blades not waxy-pruinose beneath, the rachises and costae paleaceous or fur- 

 furaceous, with or without spreading hairs; sori with capitate or spheric 

 receptacles; caudex and stipe bases bearing flat scales many cells broad. 

 Primary and secondary rachises blackish ; blades fully tripinnate, the seg- 

 ments stalked 2. A. salvinii. 



Primary and secondary rachises stramineous to yellowish or light brown ; 

 blades simply bipinnate or bipinnate-pinnatifid. 



Blades bipinnate only, the pinnules sinuate to crenate 3. 'A. marginalis. 



Blades bipinnate-pinnatifid, the segments connected by a narrow wing. 

 Segments rounded-obtuse, shallowly and broadly crenate. 



4. A. schiedeana. 

 Segments acute or acutish, sharply incised to pinnatifid. 

 Costae of pinnules thinly squamulose, nearly devoid of long spreading 

 septate hairs beneath ; primary rachis with pungent, spreading or 

 retrorse, scattered spines throughout, the secondary rachises simi- 

 larly armed 5. A. microdonta. 



126651—20 4 



