Muscti Exortic:.—Humboldtiani. 
GYMNOSTOMUM JULACEUM. 
Gymnostomum caule erecto filiformi subsimplici, foliis 
arcte imbricatis appressis ovatis serrulatis convolutis, 
nervo crasso, perichetialibus majoribus oblongis acu- 
minatis, seta longa, capsula oblonga ovata, operculo 
subulato. (Tas. XLII.) 
Has. In crepidinibus montis ignivomi Rucu-Pichincha prope 
Tablahuma, regione frigida, super basaltam, altitudine 2340 
hexapod. (Regni Quitensi.) Humboldt et Bonpland. 
Caules cespitosi, semiunciales, filiformes, rigidi, erectiusculi, sim- 
plices vel innovationibus ramosi., Folia arcte flavo-viridia, 
nitida, imbricata, undique cauli appressa, ovata, subconcava, 
serrulata, nervo insigniter incrassato sub summum apicem 
evanescente instructa. Perichetialia his multo majora, fusca, 
ext. ovata, acuminata, subserrulata, nervo crasso, int. longiora, 
circa setam convoluta, nervo magis obscuro. Seta semiunci- 
alis. Capsula oblongo-ovata, ore contracto, annulato. Oper- 
culum subulatum. 
sr aaa TIRE — 
The stems and unmagnified leaves of this little plant resemble 
those of Bryum julaceum more than any other moss; and its ge- 
neral habit is that of a Pterogonium. It is however a true Gy- 
mnostomum, as far as 1 am capable of judging without the ca- 
lyptra, which I have never yet seen, although it does not bear much 
affinity to any of the other species of this varying'genus. ‘The 
nearest is perhaps G. e@stivum; in which, as well as in this plant, 
the perichetium is highly worthy of remark; but in their leaves 
the two species are totally different from one another. 
Fig. 1, plants nat. size. Fig. 2, plants magn. Fig. 3, leaf. 
Fig. 4, 5, perichetial leaves. Fig. 6, capsule. Fig. 7, opercu- 
tum. Fig. 8, mouth of the capsule, showing the annulus. 
ae 
