78 Dixon: NEW AND RARE AFRICAN MOSSES 
MICROTHAMNIUM SAPROADELPHUM C. Mill. 
On fallen trees, Ponce, Mauritius, September, 1862, Dr. Ayres, 
Mitten’s herbarium, as M. tenellum Mitt. 
A very slender, delicate plant, with minute, narrow leaves, and 
very narrow, smooth cells, which does not agree with any of the 
described species from South Africa or the insular regions, and 
appeared quite to justify Mitten in considering it a new species. 
On comparing it, however, with the original of M. saproadelphum 
C. Miill. (Cameroons, Dusén 499), I find it identical with that. 
Mitten’s specimen is without capsules, but the setae, perichaetia, 
etc., are present, and in these and the vegetative characters it 
agrees exactly with Dusen’s plant. 
Plagiothecium nitens Dixon, sp. nov. 
Dioicum. Caespites perlati, densi, depressi, argenteo-virides, 
nitentes. Caulis repens, sat dense ramosus, ramis complanatis, 
circa 2 cm. longis, plerumque attenuatis, cum foliis 3 mm. latis. 
Folia complanato-decurva, illis P. Mildbraedii Broth. persimilia, 
paullo angustiora, asymmetrica, apice integro vel 2—3-denticulato. 
Cellulae superiores anguste thomboideae, 10-14 pu latae. 
Folia perichaetialia similia fere, sed brevius, minus acute 
acumimata. Seta brevis, 1-1.5 (raro 1.75) cm. lon a; theca sub- 
erecta vel erecta, leniter tantum curvata, cylindrica, sicca paullo 
striata. [Fic. 8.] 
Hasitat: Solai, Mt. Kenya, British East Africa, IQI0, 
R. Kemp, communicated by W. R. Sherrin. 
This plant is clearly very closely allied to P. Mildbraedii 
Broth.* from the Ruwenzori region, 
,’ applies quite well; on the 
. other hand, the cells figured are ver y sieila? to oo of the present 
plant, but they are described as “ angustissime linearibus,”” which 
is not at all applicable here. The fruiting characters, however, 
od on to present marked differences; the perichaetial bracts are 
described as “‘breviter subulatis,’ 
: ’ while here the points are rather 
wide and scarcely acute: the s S 
4 ae 
eta is “2.5-3 cm. alta,” or about 
* Wissensch. Ergebn. der Deutsch. Zentral-Afrika-Exped. 2: 169. 1907-8 : 
