SPIC1LIGIUM FILICUM l'HILIPPINBNSIUM. 
159 
LEPTOCHILUS Kaulfuss. 
23. Leptochilus heteroclitus (Presl) C. Chr. Ind. Fil. (1905) 11, 385. 
Acrostichum flagelliferum Wall. 
This species, widely distributed from British India, throughout Malaya, and 
in the Philippines especially, offers in the latter region a variability that ap- 
proaches that of Dryopteris canescens. The apices of the sterile leaves are elon- 
gated into linear lash-like appendages which are proliferous and usually take root, 
the young plants emitting a fascicle of leaves entirely different from those of 
the adult ones. Often they are not simple linear leaves, with the lateral lobes 
more or less aborted, but frequently are singularly compound, enlarged and deeply 
incised. Often the little plants are fertile, and the fertile fronds offer irregular- 
ities analagous to the sterile ones. In other characters the differences are 
frequently strongly marked, and the various forms might readily be considered 
to represent distinct species. I have enumerated below the forms, that in my 
conception of this species, should be considered as varieties or subspecies, and 
although several of them have acquired a certain stability, certain characters are 
constant in all of them, showing their close relationship to L. heteroclitus and 
probable derivation from that species. 
Var. eury basis n. var. 
Rhizomate repente, pennae anserinae crassitie, cum stipite basi squamis 
minntis dilute brunneis crispis sparso radicoso. Foliis sparsis sed appro- 
pinquatis, foliorum sterilium stipite 8 cm. longo flexuoso tenui griseo, 
fronde 13 cm. longo deltoideo-ovata, pinna terminali clecurrente et cum 
pinna laterali proxima parva plus minus concreta, basi cuneata, acumi- 
nata, nec can data nec prolifera, 8 cm. longa, 2.5 cm. lata oblonga par- 
viloba, lobis 10 vel pluribus utrinque subrotundis 3 mm. latis acute 
denticulatis, pinnis lateralibus 3 aut 4 utrinque, mediis 3 cm. longis, 1 
cm. latis cuneatis obtusis decurrentibus serrato-lobulatis, infimis valde 
postice auctis deltoideo-ovatis petiolatis nec decurrentibus, basi profunde 
incisis, caeterum serrato-lobatis. Nervis lateralibus rectis a costa ad 
marginem protensis 4 mm. distantibus, series plures areolarum valde 
irregulariarum, minores areolas nec nervulos liberos includentium con- 
tinentibus. Colore atrato, textura herbacea, opaca. Foliorum fertilium 
lamina aequilonga sed angustiore, pinna terminali 5 cm. longa lanceolata 
acuta profunde lobata clecurrente, pinnis lateralibus 4 utrinque obtusis, 
2.5 cm. longis, 1.5 cm. latis, ovatis sessilibus aut adnatis, sed pinnis infimis 
petiolatis auctis, parte terminali late cuneato-ovata lobata, pinnulis late- 
ralibus similibus minoribus. 
Mindanao, Lake Lanao, Camp Keithley (552 Mrs. Clemens) May, 1906, alt. 
660 m. 
Differing from the type by its aberrent fronds being in part bipinnate, deltoid 
at the enlarged base, posteriorly deeply incised; even the fertile fronds are some- 
times bipinnate at the base. 
