4 CONTRIBUTIONS PROM THE NATIONAL HERBARIUM. 



Cyathea delicatula Maxon, sp. nov. 



Alaophila delicatula Maxon, in ached. 



Trunk and stipe wanting; fronds relatively small, about 80 cm. broad, delicate, 

 very deeply tripinnatind ; primary rachis unarmed, slight , the under surface greenish 

 yellow, minutely puberulo-furfuraceous, glabrescent, the upper surface brownish oli- 

 vaceous and very densely strigose with jointed beadlike closely appressed brownish 

 hairs; pinna alternate, the largest 43 cm. long, 10 or 1 1 cm. broad, sessile, lanceolate, 

 acuminate, comprising about 30 pairs of straight lineardanceolate membranous spaced 

 pinnules; secondary rachis delicate, flattened in drying, this and the costa of the 

 pinnules very densely strigose above like the main rachis, minutely glandular-pubes- 

 cent below; pinnules 5.5 to 6 cm. long, 7.5 to 9 mm. broad, cut .nearly to the costa into 

 about 20 pairs of narrowly oblong nearly straight unequally rounded or subacute seg- 

 ments; segments 4 to 5 mm. long, about 2 mm. broad at the middle, the sinuses acute, 

 the margins lightly creiiate-serrulate in the outer part, the costuhe sparingly pubes- 

 cent, bearing also numerous ovate acuminate bullate reddish brown scales; veins 

 about 7 or 8 pairs to each segment, sometimes simple but mostly once forked at a slight 

 angle, concealed, setulose; sori relatively large, 5 or 6 pairs, nearer the midvein than 

 the margin, seated at the fork of the veins; indusium hyaline, very delicately mem- 

 branous, bursting irregularly, evanescent, or the inferior portion subpersistent as a 

 shallow scale; receptacle small, slightly elevated, hirsute 



Type in theU. 8. National Herbarium, no. 82(il92, collected at the summit between 

 Tactic and Coban, Alta Yerapaz, Guatemala, at an altitude of 2,000 meters, by Baron 

 H. von Tiirckheim, no. II. 1029, February, 1907. 



Cyathea delicatula, which is known only from the type collection, appears to be 

 without any very close allies. The most noteworthy features are its very narrow 

 elongate' spaced pinnules and the copious bullate scales covering the costa of the 

 segments. 



Cyathea mexicana Sehlecht. 



II. 2108. Forest near Coban, altitude 1,200 meters, February, 1908. 



Cyathea mexicana, known hitherto only from Mexico, is represented by a fair series 

 in the National Herbarium. The pinnules are uniformly at right angles and are read- 

 ily separable from the secondary rachis. 



Cyathea tuerckheimii Maxon, sp. nov. 



Trunk and stipe wanting; fronds apparently ample, at least 130 cm. broad, very 

 deeply tripinnatifid; primary rachis yellowish brown below, very densely furfura- 

 ceous with minute deciduous yellowish brown scales and armed with numerous 

 short (1 to 1.5 mm.) straight erect spines, tuberculate and glabrate with age; pinna? 

 65 cm. long, 25 cm. broad, petiolate (1.5 cm. or more), lanceolate, acuminate, the 

 secondary rachis spinescent, clothed like the primary rachis; pinnules 1 1 or 12 cm. 

 long, 1.7 to 2 cm. broad above the base, about 28 to 30 pairs below the deeply serrate 

 apex, short-petiolate (the lower ones 4 or 5 mm.), contiguous, narrowly lanceolate, 

 attenuate, borne at a right angle or those toward the base slightly retrorse, all very 

 deeply serrate (nearly to the costa); costa of the pinnules yellowish brown with a few 

 minute short hairs and numerous very caducous glossy dark brown ovate-lanceolate 

 attenuate erose scales about 2 mm. long; segments about 20 to 22 pairs, narrow, 10 to 

 12 mm. long, 3 to 3.5 mm. broad, falcate, the basal ones separate, the others somewhat 

 dilatate and connected by a narrow wing, the margins simply crenate-serrate, revolute 

 in drying, especially toward the subacute apex, the costules clothed similarly to the 

 costae, but the scales lighter in color (yellowish brown), triangular-ovate, long-acumi- 

 nate, somewhat bnllate, with a few stout curved septate whitish hairs intermixed; 

 veins of the segments about 10 or 11 pairs, forked near the base, elevated, glabrate; 

 sori large, yellowish, 6 to 9 pairs, occupying two-thirds or more of the segment, seated 

 at the forking of the veins, the receptacles conspicuous; iudusia membranous, ruptur- 

 ing irregularly, subperaistent. 



