ROBINSON: PTERIDOPHYTA OF THE HAWAIIAN IsLANDs 247 
ILLUSTRATION: PLATE 20. 
SPECIMENS EXAMINED: Hawaii, Robinson 250 V; 270V; 200 V; 
Maui, Bailey C; Robinson 310 V; Oahu, Didrichsen C; Forbes 05 
BM; Heller 2119 C; Macrae B; Robinson 76 V; 108 V; Kauai, 
Hillebrand B; Hawaiian Islands, Baldwin roga B, C; Bennett 
B; Gaudichaud B; Lydgate B; Remy 52 B; Wilkes Expedition 12 B, 
C (cotype of T. sandvicense v. d. Bosch). 
Sir James E. Smith says ‘‘Few plants of any country have 
caused more enquiry or more diversity of opinion than this fern,” 
and the variations in the Hawaiian forms of this species might 
add much material for such discussion. 
2. HYMENOPHYLLUM J. E. Smith, Mém. Acad. Turin 5: 
418. 1793 
Rootstock slender, creeping; leaves pinnatifid to bipinnatifid, 
glabrous or hairy; sori terminal upon the veins; indusium bi- 
labiate, formed by the division of the tissue of the margin of the 
leaf; receptacle seldom exserted. 
Type species : Hymenophyllum tunbridgense (L.) Sm. 
Stem upright; leaves tufted, lanceolate; leafstalk clothed with red- 
dish hairs. 
Stem creeping; leaves not tufted. , 
Leaves glabrous, the apexes usually curving downward. H, recurvum. 
Leaves hairy, the apexes vertical. 
Leaves rhomboid or obtuse-ovate, covered with reddish 
H. Baldwiniti. 
brown stellate hairs. H. obtusum. 
Leaves lanceolate, bearing simple hairs on margin and 
veins. H. lanceolatum. 
HYMENornyttum Batpwintt D. C. Eaton, Bull. Torrey Club 6: 
293. 1879 
TYPE Locatity: Oahu. 
Distrigution: On trees, above 800 m. elevation, in a lateral 
Valley of Nuuanu, which leads up to Konahuanui. 
SPECIMENS EXAMINED: ex Herb. D. C. Eaton (cotype) C; 
Baldwin 110 C; Baldwin V. 
HYMENOPHYLLUM RECURVUM Gaud. Voy. Freyc. Bot. 376. 1832 
TYPE Locatiry: Maui, Hawaiian Islands. 
a eenoN: On trees above 600 m. elevation, Hawaiian 
Slands, 
. 
