fero. Anthera mobilis ovata membranacea purpurascens apice semibifido, unilocularis, apicem columnæ incumbens. Massæ Pollinis 4, per paria cohærentes, farinaceæ, apicibus affixæ glandulæ communi emarginaturam stigmatis operienti. Ovarium oblongum: Stylus cum basi columnæ conferruminatus: Stigma solutum, horizontale subrotundum, antice concavum, apice plica duplici coarctatum, antheræ subparallelum).
Obs. The three species of which this genus at present consists agree in their anthera being unilocular after bursting, in the singular relative proportions of the parts of the perianthium, and in habit; but in some points, generally of importance in this order of plants, they differ very remarkably, especially in the form of the labellum, which in one species is even furnished with a double calcar. Corysanthes may therefore be considered as affording a proof, and many others might be adduced, of the superior importance of certain modifications of the anthera to those of the labellum in Orchideæ.
AZOLLA.
Ord Nat. Marsiliaceæ.
Syst. Linn. Cryptogamia Filices.
Char. Gen. Flores monoici.
Masc. Gemini, involucro clauso monophyllo membranaceo inclusi, (nunc solitarii femineum stipantes), ovati, biloculares, membrana exteriore transversim dehiscenti: loculo superiore corpusculis 9 vel 6 angulatis, circa axin perforatum apice demum apertum insertis: loculo inferiore sphærico clauso, sub duplici membrana materia fluida (demum pulverea?) repleto.
Fem. In diversis alis ejusdem frondis solitarii, (nunc masculo inferiore stipati): Involucrum duplex, utrumque clausum membranaceum: exterius marium simile: interius ovatum, evalve; includens Capsulas numerosas evalves, 6—9-spermas, affixas pedicellis capillaribus e receptaculo communi baseos involucri interioris ortis. Semina angulata, radiculis exsertis.
Azolla pinnata. Tab. 10.
