appearance, fo entirely accord with the Confervas, that I confefs myfelf fur- 

 prifed at their having been removed by that able author to the Tremellae, to 

 which they feem to bear a far lefs affinity. As Dr. Roth fays he could not 

 difcover any (heath in his variety of C. velutina, to which he refers Vaucher's 

 C. vaginata, I have thought it right to quote it as a fynonym with a mark of 

 doubt. 



C. vaginata grows in fmall tufts, of which the diameter of the largeft that I 

 have gathered does not much exceed a quarter of an inch, and the greater part of 

 them are in fragments of a flill fmaller fize. The filaments are cylindrical, and 

 rcfemble thofe of C. limofa, -except that they are branched, and that they are 

 enclofed in bundles within a membranous fheath, which is fo peculiar to this 

 fpecies that it is alone fufficient to diftinguifh it from every other I am ac- 

 quainted with : thefe fheaths are themfelves branched or divided repeatedly into 

 fmaller ones, at irregular diftances of various Czes ; they are narrowed at their 

 origin, and become fwollen upwards, as the filaments increafe by branching, fo 

 as fometimes to refemble a feries of Cornucopia;. The ends of the filaments 

 which are of various lengths project beyond the ultimate divifion of the fheath, 

 and they are fometimes curioufly coiled round each other. It appears probable 

 that this fpecies is propagated by the feparation of the different divifions of the 

 fheath, each of which may thus form a diftincl: and perfect plant, and Vaucher 

 goes fo far as to fuppofe that every individual filament at length becomes an 

 envelope for other filaments which are generated within them. 



In drying, C. vaginata adheres, though not firmly, to either glafs or paper, and 

 when dried, may be revived by immerfing it in water. 



A. C. vaginata, natural fize. 



B. Ditto magnified 3. 



C. Piece of ditto, magnified 1. 



X). Ditto, larger than it appeared in the microfcope. 



