Evans: HeEpaTICAE OF PuERTO Rico 199 
a slight indentation near junction, apex broad, rounded to sub- 
acute, often apiculate by a single sharp cell, margin varying from 
entire to irregularly crenulate, denticulate or serrulate, each tooth 
consisting of a single cell; lobule ovoid, 0.17 mm. long, 0.12 mm. 
wide, strongly inflated, keel more or less arched, smooth or slightly 
roughened from projecting cells, free margin involute to apex or 
beyond, sinus lunulate, apical tooth sharp and slightly curved ; 
cells of lobe plane or slightly convex, averaging 16» at the mar- 
gin, 21 # in the middle and 35 x 21 at the base, thin-walled and 
with small trigones ; ocelli commonly two, measuring 45 x 28 p, 
situated side by side near the base of the lobe and separated from 
the line of insertion by a single row of cells: underleaves distant, 
broadly orbicular, 0.17 mm. long, 0.25 mm. wide, abruptly cuneate 
at the base, apex broad, rounded or slightly retuse, margin nor- 
mally entire: inflorescence dioicous: Q inflorescence borne on a 
short branch, innovating on one side, the innovation commonly 
short and sterile, rarely floriferous ; bracts obliquely spreading, 
the lobe ovate to obovate, 0.65 mm. long, 0.4 mm. wide, margin 
sharply denticulate, lobule oblong, 0.25 mm. long, 0.1 mm. wide, 
rounded to subacute at the apex, margin entire; bracteole free, 
orbicular, 0.4 mm. long, cuneate toward base, margin entire ; 
perianth about half exserted, cuneiform in outline with slightly 
bulging sides, o. mm. long, 0.7 mm. wide, antical face 
plane, postical kee] broad and rounded, apex broad and emargi- 
nate with a short beak, lateral keels sharp, smooth or somewhat 
roughened from projecting cells, not winged, extended upward as 
broad, rounded or truncate auricles, usually more or less denticu- 
late in the upper part: (J inflorescence usually occupying a long 
branch ; bracts in many pairs (6-22), loosely imbricated, strongly 
inflated, ‘shortly bifid, the lobe obtuse, often apiculate, margin en- 
tire, lobule obtuse, keel strongly arched and often with a crenulate 
wing one cell broad ; bracteoles found throughout spike, distant, 
oblong, commonly entire: mature sporophyte not seen (PLATE 9, 
FIGURES I~16), 
On living leaves and on the bark of trees. North slope of the 
Luquillo mountains, Heller (4326, 4329). El Yunque, Evans (7, 
19,22, 55,142,162). First collected in Puerto Rico by Schwanecke 
and afterwards found there by Sintents (4, 97). The species is very 
widely distributed in the American tropics, and two type-localities, 
St. Vincent and Barbadoes, are recorded by the original authors. 
The description of the leaves and underleaves as given above 
is drawn from those which are normally developed. In many 
Cases, however, the normal branches are largely replaced by short 
