Musci Exortict.—AHumboldtiani. 
DICRANUM LONGISETUM. 
Dicranum caule subelongato simpliciusculo, foliis falea- 
to-secundis e basi late ovata longe tenuiterque subu- 
lato-setaceis, seta longa, capsula erecta oblonga stri- 
ata, struma nulla, operculo longe subulato. (Tas. 
Has. In temperatis regni Novi Granatensis, in sylvis prope Fu- 
sagasaga, alt. 1030 hexap., atque in apricis frigidis montis 
Chimborazo, altit. 2430 hexapod. Humboldt et Bonpland. 
Caules cespitosi, subelongati, inferne fibris tomentosis obsiti. 
Folia flavo-viridia, bi- trilinearia, undique inserta, falcato-se- 
cunda, e basi late ovata, longe tenuiterque subulata, setacea, 
subflexuosa, vix apice serrulata, nervo satis angusto. Periche- 
tialia basi lanceolata vaginata, Seta stricta. Capsula erecta, 
ovato-oblonga, flavo-fusca, striata, struma nulla. Operculum 
subulatum, rectum, capsulam longitudine equans. Calypitra 
- dimidiata, pallide fusca. Peristomium e dentibus 16, infra 
apicem fissis, rufo-fuscis, transversim striatis. 
7 
There are few genera whose species are so difficult to be distin- 
guished from one another as those of Dicranum. The present 
instance happily affords an exception, The capsule has no stru- 
ma; and this circumstance, together with the general figure of 
the leaves and their direction, indicates some affinity with D. he- 
teromallum ; but in this the capsule is erect, or very nearly so ; 
and when attentively examined, the leaves, in their great length 
and shape, will furnish sufficient marks of discrimination both 
from that and every other species of the genus. 
The habit of the plant is not much unlike some species of Cy- 
nontodium, and the leaves approach those of C. longiresire, 
though the stems and the fruitstalks are widely different, and our 
species has truly the teeth of a Dicranum. 
Fig. I, 1, plants, nat. size. Fig. 2, leaves. Fig. 3, capsule 
with operculum. Fig. 4, calyptra. Fig. 5, capsule with the pe- 
ristome. Fig, 6, portion of the peristome,—-magn. 
