38 Evans: HeEpatTicAE OF PuEertTo RIco 
to substratum, irregularly pinnate, the branches widely spreading : 
leaves (when well developed) loosely imbricated, the lobe obliquely 
spreading, plane or inflexed at the apex, falcate-ovate or falcate- 
rotund from a narrow base, 0.75 mm. long, 0.4 mm. wide, attached 
by a short, almost longitudinal line of insertion abruptly curving 
toward the middle of the axis in the upper part, antical margin 
more or less concave toward base, then strongly convex to apex, 
postical margin straight or slightly convex, apex acute, whole 
margin (except concave portion) coarsely and irregularly dentate, 
the teeth numerous especially along antical margin, often as many 
as twenty-five for the whole lobe, sharp, sometimes consisting of 
single projecting cells sometimes of small groups of cells, sinuses 
separating teeth lunulate; lobule inflated in basal and carinal por- 
tions, usually plane and appressed to lobe along free margin, oblong- 
ovate, 0.25 mm. long, 0.14 mm. wide, keel slightly arched, smooth 
or nearly so, free margin almost straight as far as apex, then pass- 
ing by a broad lunulate sinus to end of keel, apical tooth strongly 
curved ; leaves often poorly developed ; cells of lobe plane, with 
more or less confluent trigones and intermediate thickenings, 
averaging 15 “in diameter at edge of lobe, 24 » in the middle and 
46 x 28 4 at the base ; ocellus single, often indistinct or obsolete, 
situated in the lower part of the lobe close to the apex of the 
lobule: underleaves distant, basal portion broadly trapezoidal, 0.05 
mm. long, marginal cells six, divisions widely spreading (up to 
0.25 mm.), usually three cells long and one or two cells wide at 
the base: inflorescence dioicous: @ inflorescence borne on a very 
short branch, innovating on one side with a simple or branched 
innovation ; bracts erect-spreading, scarcely complicate, unequally 
bifid, the lobe ovate, 0.4 mm. long, 0.2 mm. wide, acute or acumi- 
nate, margin irregularly dentate to subentire, lobule 0.3 mm. long, 
0.08 mm. wide, acute or bidentate at the apex, margin as in lobe ; 
bracteole connate on one or both sides, linear to ovate, 0.4 mm. long 
o.2 mm. wide, bifid about one third with lanceolate, acuminate lobes 
separated by a narrow sinus, margin as in bracts; perianth about 
two thirds exserted, oblong-obovoid from a narrowed base, 0.6 
mm. long, 0.3 mm. wide in the middle, truncate at the apex and 
with a very short or obsolete beak, terete below, sharply five- 
keeled above, the keels projecting outward as sharp, dentate to 
spinose horns, with usually one to four teeth or spines on each: 
$ inflorescence occupying a short branch; bracts usually in three 
to eight pairs, closely imbricated, strongly inflated, shortly bifid with 
acute divisions, keel strongly arched with a narrow crenulate wing ; 
bracteoles present at base of spike, bifid with suberect divisions 
separated by a broad lunulate sinus ( p/. 6). 
