FERNS OF THE MALA Y- A S 1 AT I C REGION. 
19 
3. Lygodium scandens (L.) Sw. 
Dwarf-branch hairy, about 5 mm long, with a small terminal bucl 
buried in crinite hairlike brown scales ; pinnae usually 10-15 cm long, 
pinnate; pinnules 3 to 5 on a side, alternate, simple, deltoid-lanceolate, 
acute or obtuse, minutely crenulate, cordate or truncate at the base and 
articulate to a very narrowly winged stalk about 5 mm long; terminal 
pinnule usually palmately lobed; fertile pinnules usually smaller and 
rounder than the sterile. From both India and Xew Guinea I have 
mixtures of sterile pinnae of this species with fertile ones of L. flexuosum. 
Africa to Polynesia, north to Formosa and southern China. 
4. Lygodium polystachyum Wall. 
Rachises hairy; dwarf -branch almost obsolete, with a small scaly ter- 
minal bud; pinnae about 20 cm long, pinnate; pinnules short-stalked, 
3—5 cm long, deltoid-lanceolate, regularly. pinnatifid more than halfway 
to the costa into oblong, rounded segments, thinly herbaceous, glandular- 
hairy on the veins ; fertile segments contracted, each to one spike. 
Birina and the Malay Peninsula. 
5. Lygodium flexuosum (L. ) Sw. 
Dwarf-branch 0 to 2 mm long; pinnae pinnate, 20 cm more or less long, 
often hairy throughout, rachis usually very narrowly winged ; lower pin- 
nules long-stalked, upper ones almost sessile, stalks winged; pinnules 
entire and narrowly deltoid-lanceolate, or with basal lobes on one side or 
both (usual form), or pinnate with one pinnule on each side and each 
of them with a short, broad lobe on the basal side; ultimate pinnules or 
divisions usually 3 to 7 cm long, sometimes longer, lanceolate, usually 
acute or acuminate, truncate or cordate at base, the sterile margin finely 
serrate. 
This is the most variable species of Lygodium. Hooker and Baker in Synopsis 
Filicum state that L. salicifolium is a “form with small neat long-stalked seg- 
ments.” I can not distinguish the “L. salicifolium Pr.” collected at Chittagong 
by Hooker and Thompson from typical L. flexuosum. 
Queensland to India, southern China, and Luzon. 
6. Lygodium mearnsii C'opel. Philip. Journ. Sci. Bot. 3 (1908) 37. 
Dwarf -branch 5 to 9 mm long; sterile pinnae 15 cm more or less long, 
often wider than long ; pinnules 2 or 3 on a side, the lowest with a stalk 
1 cm or more long, pinnate, rachis winged ; pinnules 11 usually 1 on a side, 
lobed on each side at the base, and the lobe on the lower side in its turn 
lobed on one side, terminal segments lanceolate, mostly obtuse, crenate- 
serrate into broad, shallow, denticulate teeth, herbaceous, glabrous ; suc- 
ceeding pinnules smaller and more simple; fertile pinnules smaller, 
broader, and less cut, the spikes broad and fiat. 
Batanes Islands. 
