Although the authors of the Synopsis Hepaticarum, as long ago as 1845, listed 
the present species from Greenland it is known even now from very few local- 
ities in North America. Macoun, 1 in 1902, cites specimens from Labrador as 
well as from the original Greenland station, while Miss Lois Clark, 2 in 1909, makes 
the first record for the United States: namely, Paradise Valley, Mount Rainier, 
Washington where the plant was found by T. C. Frye in 1908. She likewise 
calls attention to some of the more important peculiarities of the species. The 
writer is unable to give any additional stations for the plant from the North 
American mainland, but the Cornell Party of the Peary Expedition of 1896 
collected it on the Nugsuak Peninsula of Greenland. Miss Lorenz 3 has already 
listed Hygrobiella laxifolia from Nova Scotia, basing her record on the Cape 
Breton specimens. She predicts its discovery in Maine, and it ought to be 
looked for also in the moister parts of the Rocky Mountains. 
6. Cololejeunea tuberculata sp. nov. 
Collected in March, 1915, on leaves of Trichomanes Krausii Hook. & Grev., 
on Nixon-Lewis Hammock (No. 5250), on Sykes Hammock (No. 5257), and in 
pinelands about Timms Hammock, Dade County, Florida, by J. K. Small, C. 
A. Mosier, and E. W. Small; also on leaves of Trichomanes sphenoides Kunze, 
on Hattie Bauer Hammock, Dade County, Florida, by the same collectors. No. 
5250 may be designated the type. 
Plants very delicate, pale green, often becoming bleached with age, scat- 
tered or growing in thin mats: stems prostrate, about 0.03 mm. in diameter, ir- 
regularly and sometimes abundantly branched, the branches widely spreading, 
•essentially like the stem: leaves distant to slightly imbricated, obliquely to widely 
spreading, plane or nearly so, the lobe sometimes deflexed at the apex, ovate, 
when well developed 0.18-0.2 mm. long and 0.12-0. 13 mm. wide, but often con- 
siderably smaller, gradually narrowed to an acute or obtuse apex tipped with a 
single cell, both dorsal and ventral margins rounded in the basal half and straight 
in the apical half, denticulate from projecting cells; lobule often very rudimen- 
tary, when well developed ovate, about 0.09 x 0.075 mm., strongly inflated 
throughout, apical tooth usually consisting of two cells in a row, the hyaline 
papilla at the base of the tooth on the inner surface, proximal tooth shorter 
and usually consisting of a single blunt or acute projecting cell separated from 
the apical tooth by a single cell, sinus shallow, two or three cells long; cells at 
lobe averaging about 7/4 along the margin, 10 x 8 /j. in the middle, and 14 x 8/x of 
the base, each bearing a median rounded Wart on the outer surface, 4-6^ long, 
with the wall thickened at the apex, cell-walls otherwise thin throughout; cells 
of lobule in the region of the keel with similar but shorter warts; stylus none: 
inflorescence autoicous: 9 inflorescence borne on a more or less abbreviated 
branch, innovating on one side, the innovation short and sterile and often ob- 
solete; bracts obliquely spreading, more or less complicate, the lobe ovate, 0.2- 
0.25 mm. long and 0.07-0.09 mm. wide, sometimes inflexed at the acute apex, 
1 Cat. Canadian Plants 7 : 31. 1902. 
* Bull. Torrey Club 36 : 304. 1909. 
8 Bryologist 18 : 25. 1915. 
