4 ASTOMI. [Phascum. 



THIS genus comprises not only species which are amongst the 

 most minute of the Mosses, often scarcely discernible to the naked 

 eye ; but such as are extremely dissimilar in general appearance 

 to each other. Together with their minuteness a remarkable 

 feature of the genus may be seen in the fruit, which, in the most 

 advanced state, as well as at an earlier period, shows no traces of 

 a suture, no line of separation, between the operculum and the 

 capsule. These are continuous, and the consequence is that the 

 seeds, or sporules, have no opportunity of escaping until the decay 

 of the capsule, or till it bursts in age. 



Some of the species are attached to Conferva-like branching 

 shoots, (similar to what we believe to be the origin of all Mosses) 

 as in P. stoloniferum. P. alternifolium is remarkable in the struc- 

 ture of its capsule. The fruit is sessile or pedunculated, some- 

 times appearing lateral from a prolongation of the stem just 

 beneath the fructification. The leaves vary much in form and 

 texture; loosely or compactly reticulated; furnished with, or 

 destitute of, a nerve. By means of P. bryoides the genus is allied 

 to Gy mnostomum ; and still more to Voitia of Hornschuch and 

 to Bruchia of Schwaegrichen. The former of these two is distin- 

 guished, according to its author, by the capsule being deciduous 

 together with the seta, (which, however, we believe to be the case 

 with P. bryoides) and by its large persistent calyptra ; and the 

 latter in having a mitriform calyptra. 



With the exception of Phascum nervosum, (Musci Exotici, t. 

 105. and P. splachnoides of Hornsch. in Horce Phys. Berol. t. 

 12. both natives of Southern Africa), all the other species are, 

 we believe, inhabitants of the temperate parts of the northern 

 hemisphere, always growing in a more or less tufted manner upon 

 wall-tops, banks of earth, and in fallow-fields. 



* Furnished with creeping, branched, conferva-like shoots. 



P. serratum ; shoots branched conferva-like, perichsetial leaves 

 lanceolate deeply serrated nerveless. (TAB. V.) 



Phascum serratum. Schreb. de Phasco, t. 2. Smith, Fl Brit. p. 

 1156. Hedw. Sp. Muse. p. 23. Engl Bot. .460. Dicks. Crypt. 

 Fasc. l.t.l.f.l. Turn. Muse. Hib. p. 4. Funck, DeutscU. Moose, t. 



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