VIII. ACKOSTICHE^. 



Fronds articulate to the rhizome or not so, simple, dichotomous, or 

 pinnate, when pinnate the pinnae equal-sided; sterile and fertile fronds 

 or parts of fronds distinct but not usually very different; sporangia 

 covering the fertile surface, without being collected into sori; indusia 

 therefore wanting. 



1. Fronds pinnate, or the primary venation so. 



2. Fronds simple - (59) Elaphoglossum 



2. Fronds pinnate .... (60) Achrostichum 



1. Fronds or main veins dichotomous. 



2. Stipe present, not articulate (61) Cheiropleuria 



2. Fronds sessile, articulate to rhizome J (62) Platycerium 



(59) ELAPHOGLOSSUM Schott. 



Rhizome in our species creeping; fronds simple, entire, firm in texture, 

 the fertile and sterile not exceedingly different, clothed with broad, 

 ornate scales or glabrous; veins free unless at the margin; sporangia 

 densely covering the lower surface. A large genus in tropical America, 

 sparingly represented in the Old World. Our species are epiphytes of 

 rather small size. 



1. Margin cartilaginous, not ciliate (1) E. conforme 



1. Margin ciliate. 



2. Surface glabrous (2) E. decurrens 



2. Surface somewhat scaly (3) E. Cumingii 



E. latifolium (Sw.) J. Sm. was reported by Harrington from Steere's 

 collection from Luzon: the species is usually regarded as exclusively Ameri- 

 can, and this determination was probably not quite accurate, or the 

 specimen may have been ascribed to the wrong region, as Steere collected 

 in tropical America. 



(1) E. conforme (Sw.) Schott. Rhizome woody, creeping or scandent, 

 clothed with large ovate, membranous paleae 5 mm. long; stipes 5 to 15 

 cm. high, firm, erect, stramineous, glabrescent; frond 15 to 25 cm. high, 

 1.5 to 3 cm. broad, obtuse, cuneate at the base, entire and cartilaginous 

 at the margin, coriaceous, glabrous; veins mostly once forked. 



Benguet and Arayat, Loher; Mount Mariveles, 1,200 m., Merrill 3250, 

 Copeland 1384. 



Pantropic. 



Achrostichum ophioglossoides Mett. is a small thick-leaved form collected 

 at Manila by Meyen. 



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