I 
Descriptions of Plants.] APPENDIX. 611 
fero. Anthera mobilis ovata membranacea purpurascens apice semibifido, unilocularis, 
apicem column* incumbens. Masses Pollinis 4, per paria cobserentes, farinacete, apici- 
bus affix* glandulss com muni emarginaturam stigmatis operienti. Ovarium oblongum: 
Stylus cum basi column* conferruminatus : Stigma solutum, horizontale subrotundum, 
antice concavum, apice plica duplici coarctatum, antberas 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 ot 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 con- 
sidered 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 Orclndeas. 
AZOLLA. 
Ord. Nat. Marsiliace.ce. 
Syst. Linn. Cryptogamia Filices. 
Char. Gen. Flores monoici. 
Masc. Gemini, involucro clauso monophyllo membranaceo inclusi, (nunc 
solitarii femineum stipantes), ovati, biloeulares, membrana exterior© 
transversim dehiscenti : loculo superiore corpusculis 9 vel 6 anguiatis, 
circa axin perforatum apice demum apertum insertis : loculo inferior e 
sphmrico clauso, sub duplici membrana materia fluida (demum pul- 
verea?) repleto. 
Iem. In diversis alis ejusdem frondis solitarii, (nunc masculo inferiore 
stipati) : Involucrum duplex, utrumque clausum membranaceum : 
exterius marium simile : interim ovatum, evalve ; includens Capsulas 
numerosas evalves, 6 — 9-spermas, affixas pedicellis capillaribus e 
receptaculo com muni baseos involucri interioris ortis. Semina angu- 
lata, radiculis exsertis. 
Azolla pinnata. Tab. 10. 
