OF THE ATLANTIC ISLANDS. 3 
not hygroscopic; and Brachysteleum of Hornschuch (an olde: 
name applied to the same species) he is willing to retain for the 
reception of such species as have a short seta; but these are al 
the distinetions upon the strength of which they are to be consi- 
dered coequal genera with Glyphomitrium. 
Brachyodus, Nees et Hornschuch, and Campylosteleum, Bruch 
et Schimper, owe their distinction from Glyphomitrium chiefly to 
their diminutive size; besides which, the only characters in Bra- 
chyodus are the short peristome and the plication of the empty 
capsule, and in Campylosteleum the curved fruitstalk ; for in the 
latter the peristome is similar to that of Ptychomitrium. All the 
species of these supposed genera agree in the areolation of their 
leaves, the mitriform calyptra, and in having a peristome which 
among them passes through similar forms to those observable in 
Grimmia, to which they appear to form an allied and closely related 
genus—differing in habit and areolation, but agreeing in the struc- 
ture of the peristome, the highest development of which appears 
in Glyphomitrium polyphyllum and Grimmia (Rhacomitrium) ca- 
nescens, Dill. 
Unora, Brid. 
U. VITTATA, sp. nov. Habitu staturaque U. Bruchii, foliis patentibus 
` siccitate crispatis e basi latiore subovata sensim lineari-lanceolatis apice 
obtusiusculis nervo carinatis integerrimis, cellulis basi ad latera seriebus 
singulis hyalinis quadratis interioribus ad nervum elongatis angustis, 
ad margines usque ad folii medium seriebus circiter sex cellularum 
elongatarum angustarum vittam plus minus distinctam formantibus, 
theca ovali sensim in pedunculum attenuata siccitate plicata rubro- 
fusca, peristomio U. Bruchii, calyptra ramentis paucis brevibus ap- 
pressis. 
Hab. Madeira, on trees on the mountains, Johnson. 
Different from U. crispa, Hedw., and U. Bruchii, Hsch., in its 
calyptra and in the presence of the bands of elongated cells, which 
are not truly marginal, for a single row of rounded cells forms the 
margin ; this vittation is not uniformly evident in every leaf, but 
is generally so. The rounded cells of the upper part of the leaf 
are about half the size of those of U. erispa. 
Bryvm, Dill. 
B. Norarısıı, sp. nov. Dioicum, dense cxspitosum, nitidum, foliis 
confertis patentibus ovato-lanceolatis apice latiusculo apiculo parvo 
sensim acuminatisve nervo crassiusculo in mucronem excurrente, mar- 
gine superne parce denticulato medio recurvo, cellulis basi quadratis 
oblongis deinde longioribus prosenchymaticis, perichetialibus basi 
B2 
