84 NORTH AMERICAN FLORA [Vorume 16 
acute, lightly serrate-crenate ; veins 10-12 pairs, evident, very oblique, mostly once-forked 
below the middle or in sterile segments again forked, copiously yellowish-pilose, the leaf- 
tissue between them slightly pilose; sori rather large, globose, close, inframedial, about 5 
pairs, confined to the lower half of the segment; indusium delicate, yellowish-brown, 
bursting into a few irregular subpersistent fragments; receptacle elevated, dark, capitate, 
conspicuously setiferous. 
TYPE LOCALITY: Navarro, Costa Rica. 
DISTRIBUTION: Known only from Costa Rica. 
35. Cyathea conspersa Christ, Bull. Herb. Boiss. II. 5: 260. 1905. 
Cyathea furfuracea Christ, Bull. Herb. Boiss. II. 4: 950. 1904. Not C. furfuracea Baker, 1874. 
Cyathea Underwoodti Christ, Bull. Herb. Boiss. II. 6: 183. 1906. 
? Cyathea caduca Christ, Bull. Herb. Boiss. II.'7: 271. 1907. 
Caudex erect, slender, unarmed, 4-6 meters high, 5-7 cm. in diameter, slightly palea- 
ceous at the top, the stipe-scars large, oval, about 5 cm. long, nearly 3 cm. broad (maxi- 
mui), approximate, 6-ranked; fronds ample, wide-spreading, sometimes wholly deciduous 
seasonally ; stipe 30-40 cm. long, stout, strongly arcuate at the base, duil dark-brownish, 
irregularly sulcate, armed with short (2 mm. or less) straight or retrorse conical spines 
and clothed with long-attenuate deltoid-lanceolate shining dark-brown deciduous fimbriate 
scales, these subpersistent on the upper surface; lamina ample, deeply tripinnatifid, 
broadly ovate, short-acuminate, with about 25 pairs of close alternate herbaceous pinnae, 
the lowermost somewhat reduced ; primary rachis stout, light- or dull-yellowish, deciduously 
squamulose and smooth, or toward the base sparingly muricate and deciduously paleaceous ; 
middle piinae 40-50 cm. long, 12-13 cm. broad, narrowly oblong-lanceolate, sessile, acu- 
minate, strongly imbricate, the secondary rachis stramineous or yellowish, smooth, sulcate, 
slightly araneose-furfuraceous below ; pinnules about 30 pairs, oblong-lanceolate, 6.5-8 cm. 
long, 12-15 mm. broad, apart, sessile, spreading, abruptly acuminate-candate, cut four 
fifths or more to a costal wing 1 mm. or more wide upon each side; segments 14-17 pairs, 
oblong, slightly falcate, obtuse, about 7 mm. long, 4 mm. broad at the dilatate base, 3 mm. 
broad above, separated by a narrow acute sinus, the margins conspicuously crenate-serrate ; 
costae conspicuously yellowish-strigose above, below (together with the costules) scantily 
and minutely paleaceous with brownish or olivaceous scales and obscurely pilose, with a 
few larger scales intermixed, those of the costules bullate ; veins 7-8 pairs, mostly sorifer- 
ous, simple or mostly once-forked near the base, glabrous; sori near the costule, small; 
indusium yellowish to olivaceous, delicately membranous, rupturing irregularly ; recep- 
tacle dark-brown, small, elevated, capitate, setose. 
TYPE LOCALITY : Costa Rica. 
DISTRIBUTION: Costa Rica; of general distribution in the interior mountainous regions, at 
from 1350 to 2000 meters altitude. 
36. Cyathea delicatula Maxon, Contr. U. S. Nat. 
Herb. 13: 4. 1909. 
Trunk and stipe wanting ; primary rachis unarmed, slight, the under surface greenish- 
yellow, minutely puberulo-furfuraceous, glabrescent, the upper surface brownish-olivaceous 
and densely strigose with jointed beadlike closely appressed brownish hairs; pinnae alter- 
nate, the largest 43 cm. long, 10-11 cm. broad, sessile, lanceolate, acuminate, comprising 
about 30 pairs of straight linear-lanceolate membranous spaced pinnules ; secondary rachis 
slender, this and the costae very densely strigose above like the main rachis, minutely 
glandular-pubescent below; pinnules 5.5-6 cm. long, 7.5-9 mm. broad, very deeply pin- 
natifid into about 20 pairs of narrowly oblong nearly straight unequally rounded or subacute 
segments; segments 4-5 mm. long, about 2 mm. broad at the middle, the sinuses acute, 
the margins lightly crenate-serrulate in the outer part, the costules sparingly pubescent, 
bearing also numerous ovate acuminate bullate reddish-brown scales; veins 7 or 8 pairs, 
sometimes simple, mostly once-forked at a slight angle, concealed, setulose; sori small, 
5 or 6 pairs, inframedial, seated at the fork of the veins; indusium hyaline, very deli- 
