WILLIAMS: CALYMPERACEAE OF NorTH AMERICA 383 
with stems up to 2 cm. high; stem-leaves usually 4-5 mm. long 
and about 0.65 mm. wide, nearly linear, the basal part often 
slightly narrower than the upper part, or the terminal leaves at 
times much shorter and broader, somewhat lanceolate, up to I mm. 
wide, all rather gradually acutely pointed, subtubulose and erect- 
flexuos when dry, widely spreading; almost squarrose when 
moist, with a pale, minutely serrulate or entire border of elongate, 
stereid cells (sometimes quite lacking in the apical leaves) ex- 
tending from about one third below the apex to four fifths way 
down the leaf; costa nearly percurrent, smooth on the back except 
at the slightly denticulate apex, about 60 » wide near. the apex of 
the cancellinae, in cross-section showing three or four guide-cells, 
stereid bands above and below them and outer cells not differen- 
tiated in the upper part, but more or less differentiated on the 
ventral side in the lower costa; cells in upper part of blade mamil- 
lose on. the upper, smooth or unipapillate on the under side, mostly 
hexagonal and not elongate or slightly so, the median about 8 pz 
wide by 8-10 » long, those next the costa on upper side often 
bearing, from some distance below the apex to near the cancellinae 
filiform propagulae about 0.5 mm. long, with fifteen to twenty 
cross-walls; cancellinae filling the most of the leaf-base and ter- 
minating in narrow angles next the costa one fourth to one third 
way up the leaf; perichaetial leaves scarcely differentiated; seta 
2-2.5 mm. long, bearing an erect, cylindric capsule about 1.5 mm. 
long; median exothecal cells more or less four-to-six-sided, 20-25 u 
in diameter, with thick walls; peristome and lid not seen; calyptra 
(immature and not fissured) with rather narrow base, gradually 
tapering upward and rough throughout. [Fic. 18.] 
TYPE LOCALITY: Hispaniola (Hayti). . 
DISTRIBUTION: Cuba (E£. G. Britton 5040a; Brother Leon 
3564), Hayti, Porto Rico (5197, E. G. Britton), Trinidad and 
Yucatan. 
ILLUSTRATION: Schwaegr. Suppl. 2”: pl. 17. 
Known only from the original collection until obtained in 
Cuba by Mrs. Britton. The type specimens do not seem to show 
any propagula, but these bodies readily fall off as the leaves 
become older. The species is quite closely related to the South 
American S. flexifolius Mitt., which has similar propagula, but 
the latter has larger leaf-cells and a border extending nearer 
to both the base and the less acute apex while the cancellinae do 
not form so narrow an angle upward. 
Lindberg* has given a rather full description of this species and 
* Ofv. Kongl. Vet. Akad. Forh. 21: 604-5. 1864. 
