470 Evans: THREE SOUTH AMERICAN SPECIES OF ASTERELLA 
elevated, measuring (with their surrounding cells) mostly 90-100 u 
in length and 80-90 p in width, surrounded usually by six (more 
rarely five or seven to nine) radiating series of cells with two or 
three cells in each series, radial walls slightly thickened; cells 
with oil bodies as in A. tenella; green tissue loose especially toward 
the margins, air chambers in two or three layers in the median 
portion, those of the dorsal layer sparingly subdivided by supple- 
mentary partitions and considerably larger than the deeper cham- 
bers; compact tissue occupying about two thirds the thickness of 
the thallus in the median portion, thinning out gradually on the 
sides and extending about halfway to the margins, composed of 
thin-walled cells without pits (so far as observed); mycorrhiza 
present; ventral scales ovate to lunulate, reddish purple throughout 
or sometimes with bleached appendages, marginal slime-papillae 
very short-lived, cells containing oil-bodies mostly three to five, 
scattered, appendages usually borne singly, rarely in pairs, nar- 
rowly subulate, scarcely or not at all constricted at the base, 
mostly 0.3-0.45 mm. long and 0.06—-0.12 mm. wide, acuminate, 
entire (or sometimes, according to Stephani, with a basal spine), 
the cells mostly 40-60 » long and 15-35 u wide: inflorescence 
paroicous, the antheridia forming a small and vaguely defined 
group close to the peduncle of the female receptacle: female 
inflorescence borne on a leading branch, peduncle mostly I-1.5 
cm. high, more or less purple, with small clusters of narrow paleae 
at base and apex but otherwise naked or nearly so; disc of recep- 
tacle green or yellowish, mostly 2-3 mm. across, bluntly conical 
and usually three- or four-lobed to about the middle, the lobes 
extending downward and outward, mostly eight-cleft, the divisions 
subulate, becoming free with age: capsule wall not studied (hyaline, 
according to Stephani); spores yellow to brownish yellow, mostly 
80-90 in diameter, with a thin, wavy, and minutely crenulate 
wing, 10-16 « wide along the edges, whole surface covered over 
with a very fine and irregular reticulum, the meshes mostly I-5 # 
across, formed by a system of delicate anastomosing lines, spherical 
face showing in addition a coarse reticulum with meshes 16-20 # 
across, formed of ridges similar to the wings, plane faces without 
ridges (so far as observed),-margins of wings and ridges more or 
less broadened; elaters:pale yellow, mostly 120-200 » long and 
about 6 u wide, tapering slightly toward the blunt ends, usually 
with two loosely twisted spirals throughout the entire length. _ 
Known only from Chile; the following specimen has been 
examined: | 
