Part 2, 1913] DICRANACEAE 141 
13. Campylopus Hoffmanni (C. Miill.) Ren. & Card. Bull. Soc. Bot. 
Belg. 313: 147. 1893. 
Dicranum Hoffmanni C. Miill. Linnaea 38: 592. 1874. 
Plants in yellowish, laxly cespitose tufts, with slender, hardly radiculose or divided, flexuous 
stems 10 cm. high: stem-leaves rather distantly and uniformly imbricate, erect-spreading 
all around, 15-20 mm. long, tubulose below and grooved above, from a narrowly ovate-lanceo- 
late base gradually attenuate into a long, straight, setaceous point, the lamina very narrow 
above, extending to or near the apex and serrulate about one fourth down the leaf ; costa mostly 
slightly excurrent, a little above the base about 400 u wide, scarcely one third the width of the 
leaf, smooth on the back, in cross-section below showing a row of large cells on the ventral 
side, and a median row of cells about one half as large, with a stereid-band on the dorsal side 
containing a single row of larger cells; alar cells forming prominent, red or hyaline auricles; 
cells just above the alar roundish to oblong, up to 20 u wide and 30-40 u long, those within 
with very unequally thickened walls, toward the margin becoming gradually very narrow and 
above in the broader part of the leaf long and narrow, 12 » wide by 50-80 u long, with thickened 
pitted walls, in the narrow wpper part of the leaf all elongate with somewhat thickened not 
pitted walls. 
TYPE LocaLity: In bogs of the Barba voleano, Costa Rica. 
DIsTRIBUTION: Known only from the type locality. 
14. Campylopus Brittonae R. S. Williams, sp. nov. 
Plants in extensive, rather loose, glossy, yellowish-green mats, with widely branching 
stems tomentose below, up to 7 em. high: leaves up to 16 mm. long, rather uniformly placed 
along the stems, widely spreading, flexuous, slightly secund, from a narrowly lanceolate base 
gradually narrowed to a slender, minutely serrulate flexuous hair-point; costa long-excurrent, 
denticulate and pale at the apex, at the base about five sevenths the width of the leaf and 0.65 
mm. wide, in cross-section below showing a ventral row of large cells scarcely reaching one 
half through the leaf and a stereid-band on the dorsal side with a row of differentiated cells on 
either side of the band; alar cells reddish or hyaline, forming more or less conspicuous auricles; 
cells just above short, 15-20 » long and often nearly as broad toward the costa, gradually much 
narrower toward the margin but scarcely forming a distinct border, soon becoming more or less 
obliquely elongate upward, not in straight rows, with very unequally thickened walls, some- 
times slightly pitted near the costa, and about one half up in the very narrow blade becoming 
small, oval to rhomboidal, about 6 w wide and 8-12 u long. 
Type collected on Sir John’s Peak, Blue Mountains, Jamaica, October, 1908, E. G. Brition 
1167 (herb. N. Y. Bot. Gard.). prem: 
DIstRIBUTION: Known only from the type locality. 
This species has leaves in shape much like C. Hoffmanni, but they are widely spreading and 
flexuous, with the costa much broader and the leaf-cells shorter and scarcely or not pitted. 
SAS . Campylopus praealtus (C. Miill.) Paris, Index Bryol. 
Suppl. 96. 1900. 
Dicranum praealtum C. Mill. Hedwigia 37: 227. 1898. 
Plants in robust, laxly cohering, glossy-yellow tufts, up to 24 cm. high; stems stout, 
radiculose nearly to the apex, simple or dichotomously divided, and terminating in more or 
less penicillate apices: leaves 10-12 mm. long, the older cauline bristly spreading, the younger 
more or less imbricate, from a fibrillose base ovate-lanceolate, subtubulose above, gradually 
produced into an acute, rather short, sharply dentate apex; costa about 800» wide below, 
laxly reticulate, in cross-section showing large ventral cells extending more than one half 
through the leaf and a stereid-band below enclosing two rows of rather small cells; cells of the 
leaf-blade just above the alar and toward the costa broadly oblong with much thickened and 
pitted walls, in the margin narrower and paler, forming a rather distinct border; cells above 
becoming more or less obliquely and narrowly oblong to linear, with walls much pitted in the 
broad part of the leaf-blade. 
TYPE LOCALITY: Sierra de Luquillo, Porto Rico. — 
} DISTRIBUTION: Known only from the type locality. 
