15 



SECTION lit. 



SYSTEM OF VAUCHER. 



M. Vaucher has -divided the Confervre into the fix following genera. 

 Eilofperma, Conjitgata, Hydrodiclyum, Polyfpermum, Batrach • fermum, and Pro- 

 llfera. In purfuance of my plan, I fliall now give an outline of his ideas of the 

 general fructification of each of thefe, with which I (hall incorporate the few 

 obfervations I have myfelf made on the fruit of their refpective fpecies. 



The Ectospermes are thus defined, " Les organs fkondans font txteriurs, 

 et les grains font porties fur des pedsncles qui partent d'une lube ramife." 



The generic name Ectfperma, has been changed by M. Decandolle to 

 Vaucheria, and the genus is with this alteration adopted in Englijh Botany with 

 the following eflential character, " Anthem, aivl-Jhaped, incurved. Capfules 

 adjoining to the Anthem, ovate, ftngle fecdcd, in pairs or fAitary." 



M. Vaucher has traced the growth of thefe plants, through all their ftages, 

 and fatisfactorily proved what the obfervations of Mr. Borrer have fince fully 

 confirmed, that they are propagated by the germination of their granules. Al- 

 though, in his fpecific defcriptions, M. Vaucher has called thefe granules naked 

 feeds, yet his remarks, added to my own, induce me rather to believe that 

 the grains of all the Vaucherht are mnnofpermous capfules, as Dr. Smith has 

 defcribed them. I wiih, however, rather to fubmit this as a matter for future 

 obfervation, than to e>;prefs a decided opinion upon the fubje£l, though having 

 circulated a theory founded on a contrary opinion among my Botanical friends, 

 I think it rreceffary to fhev,- how I was led into this error. The fpecies figured 

 at T. 74, under Muller's name of C. veftcata, is Vaucheria feffdis, but I could 

 not then difcover any aniherae, and as Vaucher's grains are reprefented to be 

 naked leeds, and as he had not mentioned the capfules or bladder-like vcficles 

 which abounded in my fpecimens, I concluded that it mull be a different fpecies. 



