STANDLEY TREES AND SHRUBS OF MEXICO. 41 



lute; sori large, 6 to 9 pairs, seated at the fork of the once-branched veins, the 

 irregular divisions of the membranous indusium subpersistent. 



3. Cyathea princeps (Linden) E. Mayer, Gartenflora 17: 10. 1868. 

 Cibotium princeps Linden; E. Mayer, Gartenflora 17: 10. 1868, as synonym. 

 Cyathea bourgaei Fourn. Mex. PI. Crypt. 135. 1872. 



Cyathea munchii Christ, Bull. Herb. Boiss. II. 7: 413. 1907. 



Veracruz and Chiapas, the type from the Volcano Tuxetla, Veracruz. Also 

 in the mountains of Alta Verapaz, Guatemala ; ascribed also to Costa Rica, but 

 probably erroneously. 



Caudex erect, stout, said to reach a height of nearly 20 meters ; fronds at 

 least 4 meters long; stipes 1 to 1.5 meters long, together with the yellowish 

 primary and secondary rachises densely clothed with narrow, yellowish, spinu- 

 lose, spreading or retrorse scales ; blades broadly ovate, 2 to 2.5 meters long, 

 tripinnate ; pinnae oblong-lanceolate, acuminate, up to 1 meter long and 35 cm. 

 broad, long-stalked ; pinnules very numerous, approximate, linear-oblong, up to 

 18 cm. long, narrowly long-acuminate, the costa minutely and deciduously 

 scaly beneath ; segments 25 to 32 pairs, linear-oblong, dilatate, falcate, suben- 

 tire, acutish, pruinose beneath, the costa with a few minute, simple or cleft 

 scales ; sori large, 6 to 9 pairs, the coriaceous indusium splitting into 2 to 4 per- 

 sistent saccate lobes. 



4. Cyathea jurgensenii Fourn. Mex. PI. Crypt. 135. 1872. 

 Mountains of Oaxaca and Veracruz, the type from Oaxaca ; rare. 



Caudex presumably erect and several meters high ; fronds ample, the blades 

 bipinnate-pinnatifid, 1 meter broad or more, the primary rachis pale, minutely 

 spinose ; pinnae oblong, abruptly acuminate, mostly petiolate, up to 65 cm. long, 

 the rachis smooth or nearly so, glabrate beneath ; pinnules about 25 pairs, 

 articulate, petiolate, deltoid-lanceolate, long-acuminate, 10 to 12 cm. long, very 

 deeply pinnatifid, the costa nearly or quite glabrous beneath; segments 18 to 

 20 pairs, close, oblong, falcate, acute, obscurely crenate-serrate, bright green 

 and nearly or quite glabrous on both surfaces; sori 4 to 8 pairs, apart from 

 the costule, only the fiat lobate basal portion of the pale yellowish membranous 

 indusium persistent. 



5. Cyathea trejoi Christ, Bull. Herb. Boiss. II. 5: 733. 1905. 



Known only from San Pablo, Chiapas, altitude 1,500 meters, the type locality. 



Caudex erect, long and slender, very spiny; fronds rather small, the primary 

 rachis stout, smooth, stramineous or reddish, shining; pinnae articulate, easily 

 deciduous, narrowly ovate, acuminate, 30 cm. long or more, long-petiolate ; 

 pinnules about 20 pairs, approximate, readily separable, lanceolate, 5 to 6 cm. 

 long, cut nearly to the scantily pilose costa ; segments about 15 pairs, oblong, 

 subfalcate, obtuse, slightly dilatate, crowded, light green beneath, lightly 

 crenate ; sori 2 or 3 pairs, very small, basal, close to the costule, the delicate 

 indusium grayish. 



6. Cyathea mexicana Schlecht. & Cham. Linnaea 5: 616. 1830. 

 Cyathea hexagona Fge & Schaffn. ; Fee, Mem. Foug. 8: 111. 18.57. 

 Cyathea articulata Fee, Mem. Foug. 8: 111. 1857. 



Cyathea glauca Fourn. Mex. PI. Crypt. 135. 1872. Not C. glaiica Bory, 1804. 



Alsophila mucronata Christ, Bull. Soc. Bot. Belg. 35: 178. 1896. 



Cyathea arida Christ, Bull. Herb. Boiss. II. 6: 180. 1906. 



Veracruz to Chiapas, the type from Jalapa. Also in Guatemala (Alta 

 Verapaz), Costa Rica, and western Panama, at 120 to 1,300 meters. 



Caudex 3 to 10 meters high, unarmed ; fronds 2 to 3 meters long, the stipe 

 clothed at the base with brown acicular scales about 1 cm. long and armed 

 with a few sharp conical shining black spines ; blade 1.5 to 2.5 meters long, 



