42 CONTRIBUTIONS FROM THE NATIONAL, HERBARIUM. 



oblong, bipinnate-pinnatifid ; primary rachis stout, usually castaneous, decidu- 

 ously puberulo-furfuraceous ; pinnae oblong-lanceolate, acuminate, up to 85 cm. 

 long, short-petiolate, deciduous; pinnules articulate, readily separable, 30 to 

 40 pairs, often distant, oblong-lanceolate, up to 10 cm. long (usually smaller), 

 sessile or short-stalked, the costa beneath bearing a few antrorse hairs and 

 deciduously squamulose toward the base; segments narrowly oblong, oblique, 

 subfalcate, obscurely serrulate, connected by a wing 1 to 1.5 mm. broad on 

 each side of the costa ; sori 4 to 7 pairs, close to the costule, the divisions of 

 the pale membranous indusium mostly fugacious. 

 A variable species. 



2. HEMITELIA R. Br. Prodr. Fl. Nov. Holl. 158. 1810. 

 References : Maxon, The North American species of Hemitelia, subgenus 

 Cnemidaria, Contr. U. S. Nat. Herb. 16: 25-49. j)l. 18-26. 1912; Maxon, The 

 North American species of Hemitelia, section Euhemitelia, Contr. U. S. Nat. 

 Herb. 17: 414-^20. pi. 17-22. 1914. 



Similar in general to Cyathea, but having the indusium inferior, more or 

 less hemispherical, and varying from lobed to lacerate ; or, in the American 

 subgenus Cnemidaria, the plants mostly with short ascending trunks, coarse, 

 succulent, pinnate or rarely bipinnate fronds, free-veined or not, the indusium 

 hemispheric, concave, often lobed. 



Blades fully bipinnate, the pinnules sessile and very deeply pinnatifid ; indusium 

 deeply lacerate, the divisions with long filamentous apices. 



1. H. costaricensis. 

 Blades pinnate, the pinnae lightly crenate to pinnatifid ; indusia entire or 

 merely lobed. 

 Veins all free ; pinnae pinnatifid at least two-thirds the distance to the costa, 



the segments oblong, acuminate, aristate 2. H. apiculata. 



Veins (basal) united by a transverse veinlet, a single row of costal areoles 

 thus formed ; lobes or crenations low or short, not acuminate. 



Pinnae lightly crenate-serrate, decurrent 3. H. decurrens. 



Pinnae deeply crenate to crenately lobed, not decurrent. 



Larger crenations 5 to 7 mm. broad, acute distally ; pinnae 2.5 to 3 cm. 



broad 4. H. mexicana. 



Larger crenations 9 to 12 mm. broad, rounded ; pinnae 3.5 to 4.2 mm. 

 broad 5. H. lucida. 



1. Hemitelia costaricensis (Klotzsch) Mett. ; Kuhn, Linnaea 36: 159. 1869. 

 Cyathea costaricensis Klotzsch; Kuhn, Linnaea 36: 159. 1869, as synonym. 

 Mountains of Veracruz and Chiapas. Also in western Guatemala and in 



Costa Rica (the type locality), ascending to 1.000 meters. 



Caudex erect, 1 to 2 meters high, or more ; pinnae narrowly oblong, acuminate, 

 mostly 50 to 70 cm. long ; pinnules 23 to 27 pairs, mostly sessile, linear-oblong, 

 long-acuminate or attenuate ; segments 20 to 23 pairs, narrowly oblong, subfal- 

 cate, acute, connected by a narrow costal wing. 



2. Hemitelia apiculata Hook, in Hook. & Baker, Syn. Fil. 29. 1868. 

 Mountains of Oaxaca, the type locality. 



Blades 35 to 50 cm. broad; pinnae narrowly oblong-lanceolate, 18 to 30 cm. 

 long, 2.5 to 4.5 cm. broad below the narrowly long-acuminate apex, pinnatifid 

 at least two-thirds tlie distance to the costa, the sinuses linear and vei'y 

 acute. 



3. Hemitelia decurrens Liebm. Dansk. Vid. Selsk. Skrivt. V. 1: 285. 1849. 

 Hernistegia decurrens Fourn. Mex. PL Crypt. 135. 1872. 



