NortH AMERICAN SPECIES OF LESKEA ATT 
two rows of pellucid cells, shed with the operculum; operculum 
conic, straight or obliquely beaked; calyptra cucullate, reaching 
to the base of the capsule ; spores smooth, 10-13 4 wide, mature 
msummer. On rocks and rotten wood. (PLATE 16, FIGS. 55-68.) 
TypE LocaLitry: Montana; type collected by Mr. R. S. 
Williams, on Tenderfoot or Belt Mountains, Sept. 9, 1891 ; now 
in the Herbarium of the New York Botanical Garden; also col- 
lected by Mr. Williams at Columbia Falls, Mont., and by Prof. 
Holzinger in Minnesota. 
In general appearance L. Williamsi resembles the smaller 
forms of L. tectorum, from which it differs, however, by its nar- 
rower, longer acuminate, often serrate leaves, its longer median 
cells, its broader, strongly reticulated endostome and its striate- 
plicate perichetial bracts. Named in honor of my friend Mr. R. 
S. Williams. : 
12. Leskea Williamsi filamentosa var. nov. 
In thin loosely spreading or somewhat intricate tufts, pale 
green passing to yellowish green or reddish brown; stems pros- 
trate, defoliate or with a few rudimentary leaves, sparingly 
branched ; branches filiform, diffusely spreading, 2-5 cm. long; 
branchlets flagellate, brittle, broken when dry: larger branch- 
leaves narrowly ovate-lanceolate, long-acuminate, erect, not 
plicate, entire or serrulate above, 0.15—-0.2 mm. wide, 0.3-—0.5 mm. 
long ; costa thin, commonly marked by 3 or 4 rows of enlarged 
cells, disappearing below the middle ; leaf-cells smooth, clear, not 
uniform; median cells oval-rhombic to linear-rhomboidal, 2-4 
times as long as wide; alar quadrate, in 3 or 4 rows; leaves of 
branchlets similar, smaller, sometimes rudimentary: sterile. 
Type of variety collected by Mr. L. F. Anderson on rocks near 
Lahoon, Idaho. Drummond’s Musci Americana 279, in part ; 
Brandegee’s Mosses of Southern Colorado 38. 
This delicate little moss appears to have beena standing puzzle 
for several years. It was found in some of the sets of Drum- 
mond’s Musci Americana mo. 279, but not in all, and was dis- 
tributed as Hypnum catenulatum. Some of the other sets of this 
number, but not all, contained Heterocladium heteroptertoides files- 
cens, a moss it closely resembles, but which differs in being papil- 
lose. Some years ago Mr. Gepp sent me from the Natural History 
Museum in London a portion of one set of Drummond’s 279 
bearing the name of Hypnum graveolens Wils. It therefore 
