606 FILICES. [ Asplenium. 
eo Ps share the cca A. Pasty ctum. There are two forms, both on Hawaii and 
Kauai; one above dese , the frond dark green See narrow, cnlnae: jpebot be hee: 
the othe salen with the nee teens ovate-lanceolat 
var. Kauaiense. — Ultimate segments very narrow, less than 1/2” 
broad, pointed or truncate, with only one vein and a sorus which fills 
its entire width. Fronds of variable dimensions, one of the largest size 
and others only 8‘ long by 4’ broad. 
Kauai! with the preceding (Kn.). 
he species is not reported from elsewhere. Its position is not quite clear, but pro- 
bably it is connected with A. furcatum, although it cannot be denied that a gap exists 
between the two species. It would furnish the natural aba aii of the group of 
A. contiguum, as A, sphenotomwm does to that of A. subfalea 
27. A, Adiantum nigrum, L. — Hook. Sp. Fil. UL, 187. — Rhizome 
short, aa horizontal, rising at the end, thickly studded with the 
remnants of old stalks. eee crowded, chestnut-brown, polished, 6—12‘ 
long, clothed at the base with dark-brown glossy linear hair- pointed 
Beales of about 3” in cava Rhachis compressed, greenish in its upper 
n. Frond stiff chartaceous, ae above, deltoid or ovate, or 
rarely ovate-lanceolate, 4—8‘ < 3—7‘, bi-, tripinnate. Pinnae alternate, 
8—11 stipitate ones on a side, pee Bah the lowest ovate to ovate- 
lanceolate, on stalks 2—6, with an abscisso-truncate base and a 
margined rhachis. Secon pinnae lanceolate, the largest 1—1'/2’ long, 
stipitate with an obliquely cuneate base, and cut down to a mostly winged 
pinnules which are 1!/s—2“ broad and sharply dentate, often almost 
spinulose, or again incised. Veins close, at very acute angles (5—30°), 
with a deliquescent midrib. Sori copious, 1‘‘ and less in length, closely 
imbricate in 2 rows next to the costule, occupying about two thirds of the 
width of the pinnule, confluent at last. Invol. firm, broad, rather acute 
at the ends. — Milde, Fil. Eur. et Atlant. p. “ 
Hawaii! Maui! Kauai! Bite 4000—7000 ft. above sea. Nat. name: «Iwaiwa». 
Those forms with narrow acute segments are like Haak: Syst ented A. acutum, Bory; 10 
others the segments resemble ‘ie of A. argutum, Kaulf. and A. obtusum, Kitaib. 
~ var. — Frond ovate, small, much shorter than the stipes, stiff-coria- 
ceous, dark-brown when dry, tripinnate. Pinnae patent. Teeth of seg- 
ments short or wanting. Sori very close. Invol. rigid. . patens, 
Gaud. in Bot. Freye. P- 320 = he eee much like push of the 
at: 
Hewat Mani: from iiss s9008 ft. above the 
The species extends over W. and S. Euro the a tantls islands, Algiers, Abyssinia, 
8. Africa, Asia Minor and the Reese regions of central and southern Asia. 
Group of A. polyphyllum. Nos. 28—30. 
labrous ferns. Rhizome short ~ thick, creeping, with few small, ovate- 
Acteabintn, dag bes transparent, cystopter eo at the end. atin jurid- brown, 
deeply grooved, naked. Frond polpalchoss. ou proliferous, of delicate texture, dark- 
