28 



The Ofcillatorl*, beddes their general accordance in flruclure, are connected 

 in different points by C. diffiliens and confervicola with the other Conferva, nor 

 can I, with all due deference to the opinion of M. Vaucher, allow myfelf to 

 doubt that the propriety of retaining them among the fubmerfed Algx in the 

 vegetable kingdom will be admitted by almoft every Naturalift, and efpecially 

 by thofe who make this department of Botany their ftudy. 



To conclude, although I cannot give implicit affent to all M. Vaucher's obfer- 

 vations and deductions, yet the greater part of his phyfiological difcoveries are 

 fo well eflablifhed and fo important, that they form a memorable epoch in the 

 hiftory of the fubmerfed Algse. He has the credit of having firft raifed a 

 Conferva from feed, and of having traced it through the different flages of its 

 growth, and, to mention one only of his many difcoveries, that of the wonder- 

 ful propagation of C. reticulata, is in itfelf fufficient to render his name refpecl- 

 able, as long as fcientific merit continues to be held in efteem. 



SECTION IV. 



SYSTEM OF DECANDOLLE. 



I now turn to Decandolle, whofe arrangement of the fubmerfed Algx in the 

 Flore Francoife, and Flora Gallica, is however hardly worth notice. It is principally 

 formed by incorporating the two foregoing fyflems, with much alteration but 

 little or no improvement in their genera, as will be fufficiently fhewn by the 

 following outline of his arrangement. 



Nostoc. — Integumentum virefcens memhranaceum intus fanlum gelatina 

 mucofa filamentis momliforinibus intertexta. 

 In M. Vaucher's fyftem, Tremella conftitutes an order which is referred to 

 the animal kingdom, and comprifes tlve two genera of OfcilLitoria and Nojloc. 



