THE GENERA OF MOSSES. 
43 
Obs. To this tribe belong all Hedwig''s Gymnostomii 
(excepting Sphagnum), and Palissot's section of " Les 
Apogones urne tuhuUe^'' with the exception of TetrapMs, 
which that author unfortunately supposed to be destitute 
of teeth ; not having seen the true operculum, he mistook 
the peristome for that part, — " se divisant en quatre por- 
tions egales dentiformes permanentes." 
Gen. V. Gymnostomum, Hedw. Schreb. 
Fruct. Calyptra dimidiata, magna, vel thecae appressa 
vel inflata, et tunc interdum 4-angulo-pyramidata, persis- 
tens et maturitate medio latere rumpens sic pseudo-mitrge- 
formis. Seta terminalis innovatione quandoque quasi late- 
ralis, plerumque foliis perichsetialibus multo longior, thecas 
subconcolor, rigida, stricta aut flexuosa, in una tamen spe- 
cie pallida, crassa, carnosa. Apophysis raro uUa ? Theca 
integra subglobosa hemisphserica, turbinata, ovata, oblonga, 
aut cylindracea, etiamve angulata sequalis, aut quandoque 
sic medio subconstricta ut quasi apophysata, in speciebus 
diversis varians, sed in eadem plerumque at non semper 
constans ; ore interdum contracto sed ssepius amplo, nudo, 
in quibusdam tamen annulo gaudente, brunneo-fuscescens, 
laevis, striata vel sulcata. Operculum deciduum, thecae con- 
color, obliquum, rostratum, conicum aut mammillatum in 
quibusdam acutum, in aliis obtusum, semper integrum, 
Peristomium nullum. Columella aetate plerumque theca 
brevior, interdum longior et operculo adnatum, saepius fili- 
formis vel subclavata, stricta, rarius ampla, obconica vel 
potius infundibuliformis. Sporulce valde variantes. 
Char. Diff. Calyptra dimidiata. Seta terminalis. Theca 
ore nudo. 
