18 



portant difcoveries on other Confervce, merely confirms the foregoing obfer- 

 vations, and contains but little new on the Conjugate. 



In the fpring of 1802 I difcovered, that at a certain period of their growth, 

 fmall tubes are protruded from the fimple filaments of C. nitida; that thefe unite 

 with the fimilar tubes of other contiguous fiiaments ; that the grains of the one 

 being emptied into, coalefce with the grains of the other filament, and thus 

 cor.ititute the C.jugalis of the Flora Danica* I alfo found that this ftrange 

 property is not confined to this fingle fpecies, but that the C. genujiexa of Roth 

 is formed in like manner by an union among the fimple filaments of Muller's 

 C. ferpentina, and I traced thofe of C. fpiralis from a fimple to a conjugated 

 ftate. In the fummer of the fame year, Mr. Woods found C. bipunclata with 

 the filaments conjugated, and the fuppofed originality of thefe difcoveries 

 ail'irded me great pleafure, being then quite ignorant of M. Vaucher's con- 

 tinued application to this tribe. At length the appearance of his Hijlolre cles 

 dtiferves d'eau douce, at Geneva, in 1803, fhewed that \vc had arrived at a 

 knowledge of the Conjugaia, and formed nearly the fame conclufions refpe£iing 

 them, almoft at the fame time, and quite independently of each other. 



I have fince difcovered the feeds of C. gennjiexa ;. they are large and globular, 

 and not formed within either filament, as in C. juga/is, but in the connecting 

 tube, which thereby becomes greatly diftended, as is represented in my fup- 

 plementaiy plate. M. Vaucher could not difcover the feeds of this fpecies, and 

 of the nature of his obfervations recorded in the following pafiage, I cannot 

 form any conjecture. " Depuis Je moment ou j'ecrivais cctte defcription, j'ai 

 vu germcr cette conjugee; elle nait d'une maniere fort ditferente de toutes Ies 

 autrcs : la matiere ne pafle pas d'un tube a un tube voilin, nuis chaque logo 

 fournit elle memc une jeune plante ; le tube exterieur qui fe trouve renferme, 



■ \Mien I firft made the drawings and defcriptions of C. nit;Ja and jngalu, 1 had not the lead 

 idea that they belonged to the lame fpecies, and it was unfortunately not tilr juft after my firft 

 Fafciculus had been given to the printer, that I was fully fatisficd on this fubje:t. My defcription 

 of C. spiralis, and the drawing B which was afterwards added, will, however, fufficiently prove that 

 J had even then arrived at a knowledge of this curious property. 



