464 Best: REVISION OF THE 
of trees, on rotten wood, more rarely on stones, rocks or the 
ground, in damp shady places. Stems prostrate, usually radicu- 
lose, sometimes paraphyllose, pinnately to fasciculately branched, 
rarely stoloniferous ; central strand usually small, sometimes rudi- 
mentary or none ; leaves not heteromorphous, often papillose, ovate 
to ovate-lanceolate, acute, acuminate or obtuse, usually unicostate, 
sometimes shortly bicostate, nearly or quite entire (excl. L. den- 
ticulata) ; \eaf-cells somewhat uniform, median quadrate-hexagonal 
to oval-oblong, rarely elongated: pedicels smooth: capsules 
usually straight and erect, sometimes curved, oval to subcylindric, 
annulate; teeth well-developed, lanceolate-linear, divisural line 
and lamellae rarely absent ; endostomial band narrow, about one 
fourth to one sixth the length of the teeth ; segments linear, often 
keeled and cleft; cilia usually none or rudimentary ; opercula 
mammillate to long conic, rarely rostellate ; calyptrae cucullate, 
smooth. 
Leskea, written Leskia by Hedwig and so named in honor of 
Professor Gottfried Leske of Leipzig, formerly contained a large 
number of species which in more recent times have been divided 
up and placed under other genera. Leskea paludosa (1793); 
usually regarded as a variety of L. polycarpa Ehrh., L. gracilescens 
(1801) and ZL. obscura (1801) are the only Hedwigian species now 
recognized as belonging to this genus. As Leskea was founded 
in 1782, neither of these species could have been the first to have 
been described under it, and if the claim is allowed that the first 
species described under a genus is the type of that genus, it 
follows that the name Leskea or Leskia must displace that of some 
other genus and unless otherwise provided for, a new name must 
be given the one under consideration. The usually accepted type 
of Leskea is L. polycarpa, and since both the name and the type 
have had the sanction of all recent authorities the author of this 
revision feels constrained likewise to accept them even at the risk 
of having his citations subsequently overturned by some one less 
conservative than himself, 
Key to the Species. 
EULESKEA : leaves papillose, costate; median cells usually isodiametric ; peristomial 
teeth abruptly incurved from a bulging base when dry. 
Leaves ovate-lanceolate, acute to acuminate, more than twice as long a5 wide. 
Leaves more or less secund ; leaf-cells distinct. 
Capsules straight ; operculum short-conic. L. polyearys 
Capsules curved ; operculum long-conic. L. arenicola. 
Leaves straight ; leaf-cells small, indistinct : capsules straight, erect. 
L. microcarfe- 
