450 BENEDICT: ANTROPHYUM 
from the complete costa, open along the margin ; costa and areo- 
lation superficially indistinct. 
Mexico to Costa Rica. 
Antrophyum ensiforme occupies a rather anomalous position in 
the genus. Moore in 1857 made it the basis of a new genus, 
Scoltosorus, giving the following reasons based on Hooker's de- 
scription and figure. ‘‘ This plant having neither netted veins nor 
netted sori, cannot possibly belong to Antrophyum.” His misap- 
prehension regarding the venation was due to the fact that in the 
original description no evidence of a secondary venation was shown. 
But a distinct difference in soriation really exists. In Awan- 
trophyum, the soriation consists of series of lines which usually 
branch several times, and may anastomose considerably. In im- 
mature fronds or in the narrowest specimens, the lines may be 
simple, but the relationship is obvious. In Sco/éosorus, the soral 
lines are simple or usually only once-forked, and at a glance appear 
different from the normal type, although probably derived from it. 
Another distinctive character is found in the paraphyses which 
are present in no other American species. These, however, do 
not differ essentially from one type found on some of the Old 
World species and may be indicative of a paraphysate ancestry for 
all the present species. 
The character of greatest differential value known at present Is 
found in the diplanate spores which entitle the species at least to 
rank as a subgenus. Judging from external characters, anatomical 
differences exist as well which would further distinguish it from 
the typical species. 
2. ANTROPHYUM LINEATUM (Sw.) Kaulf. Enum. Fil. 199. 1824. 
Flemionitis lineata Sw. Prodr. 129. 1788. (Type from Jamaica.) 
Vittaria lanceolata Sw. Gesell. Naturf. Freund. Neue Schr. 2: 
7 133. PF 2 1960. 
Polytaenium laceolatum Desv. Prodr. 1 Pas 827. 
Loxogramme lineata Presl, Tent. 215. 1836. 
Polytaenium lineatum J. Sm. Jour. Bot. Hook. 4: 68. 1841. 
Spores triplanate ; paraphyses wanting ; sporangia in three oF 
four long grooves on each side of and parallel to the costa, rarely 
interconnected : fronds linear-lanceolate, 43 x 1 cm. and 43 X 1-5 
cm. (maximum), long-tapering, sessile, membranous ; areolae long 
