13 



with the Batrachofperma, and the latter approach fome other families of the 

 Co'iferv/e by fo many points, as to render the attempt to feparate them extremely 

 difficult. The gelatinous nature and appearance of the filaments is not fuf- 

 ficient, nor arc the fine tranfparent proceiTes into which their ramuli are drawn, 

 for thefe may be alfo obferved in C. protenfa, v'.vipara, and fome other Conferva. 

 Although this affinity is fo ftrong, yet as none of the Rivularia have ever been 

 nublifhed under the latter name, I have not thought it neceffary to notice them 

 in my general fynopfis.* Dr. Smith, milled by fome apparent refemblance in 

 their ftruclure, has publifhed fome of the Fuel, and even Tremella, under this 

 name, but I truft it will not be found neceffary to retain them, or the Rivulari* 

 can no longer be regarded as a natural family. 



Linckia. — Subjlantia gelatinofa, byalina, integumento membranaceo hyalino 

 induta, farcla f: ufltfi.ationum granulis in tineas curvatas moniliformet 

 crdinatis. 

 Micheli ufed Linckia as a generic name for thofe Tremella with which he was 

 acquainted, and in thefe he obferved that the granules were arranged in regular 

 lines. Dr. Roth, however, carrying his refearches farther, difcovered that in 

 fome only of the Tremelld the feeds are thus arranged, but that in others they 

 are fcattered throughout the internal mucus without apparent order. He has 

 therefore feparated the former from Tremella, and with them conftituted the 

 prefent genus, retaining Micheli's original name. Five fpecies have been afcer- 

 tained, confiftii<g of Tremdla trjlcc and uiruulata; two recently difcovered 

 fpecies, and Ulva fruniformis, which had been before removed to the Tremella 

 by Mr. Woodward. 1 he plant which Dr. Roth fuppofes to be U. prunifonnis 

 of Linnaeus, is however efientially different from that figured in Englijb Botany 

 (t. 968,) with the fame name, and which Mr. Hooker informs me is Rivularia 

 anguWa of the Caialeila Botanica. Linckia pruniformis is not known to be a 

 Britifh fpecies. 



* I have never feen a recent fpecimen, but I prefume from the defcription, that C. ethinulata o! 

 Eng. Bot. t. I37£, belongs to this family. 



