Musct Exorici.—Aichardiani. 
DICRANUM? FALCIFOLIUM. 
Dicranum ? caule elongato ramoso, foliis verticalibus 
distichis inzequalibus falcatis acinaciformibus, seta ter- 
minali, capsula ovato-pyriformi. (Tas. LX XXII.) 
Fissidens falcifolius. Schwaegr. Suppl. v. 2. p. 9. 
Has. In insula Borbonie. D. Prof. Richard. In Hispaniola. 
Thuillier, arboribus innatum. 
Planta valde singularis et vix rite hujusce generis. Calis vix 
unciam longa, erecta, flexuosa, ramosa. Folia perpulchra, 
aureo-flava, nitidissima, caulis duobus lateribus inserta, verti- 
calia, exacte disticha, plana, falciformia, integerrima, apice 
acuta, nervo arguto, fusco, propre marginem inferiorem, per- 
cursa, Perichetialia angustiora, minus falcata, basi concava. 
Seta terminalis, subuncialis, flexuosa, rufa. Capsula rufo- 
fusca, ovato-pyriformis, erecta. Operculumconicum, subob- 
tusum. Calyptram Peristomiumque non vidi, 
1 am indebted to the learned Professor Richard of Paris for 
specimens of this most remarkable and beautiful moss, whose 
habit at first sight certainly resembles those species of Dicranum 
which Hedwig and most of his followers have called Fissidens, 
and in that genus Schwaegrichen has already placed it: He, 
however, appears to have been equally unfortunate with myself 
in not being able to describe the Peristomium. Besides the 
curious form of the leaf, much more scymitar-shaped than that 
of H, trichomanoides, there is a striking peculiarity in the nerve, 
which in most mosses is placed in the centre of the leaf, whilst 
here it runs close along the lower margin; in this respect ap- 
proaching the structure of the leaf of the Fissidentes, but 
wanting the dilated and conduplicate base. Here too, unlike the 
species of that genus, the leaves spring alternately from the 
anterior and posterior sides of the stem. 
Fig. 1, plant, nat. size. Fig. 2, single plant. Fig. 3, portion 
of a stem with leaves. Fig. 4, single leaf, Fig. 5, sissies 
ditto.—magn. 
