the generic Cbara&tr ofUha, GrV. 49 



to their place of growth by fame point of the under iuif.icc. The 

 greater part are very much attenuated immediately above the bafc, 

 but fuddenly dilate, and are divided into numerous fegments, which 

 are always of the fame fubftance throughout. The filiform and 

 comprcfled Uhcc are cither fimple or branched; but the branches- 

 are merely divifions of the frond, which may therefore ftii&ly be 

 called continuous or uniform. The fructification of thefc is un- 

 known, excepting only the Ulva d'uiphana, and rubra of Hudfon ; in 

 the former of which it confills of numerous minute grains or feeds, 

 difperfed throughout the whole internal fubftance: the fructifica- 

 tion of the latter has not yet fallen under the obfervation of the 

 author. Amongft the membranaceous Ufa*, the ptivotiia, coccmca, 

 dichotoma, atomaria and liguiata t exhibit a fructification, confiding of 

 numerous minute grains or feeds, thickly fcattered 00 both fides 

 immediately under the epidermis, fometimes crowded, but moftly 

 fingle. The fructification of the Licluca, lati/Jima, comprcflh, umbili- 

 caia, and lactniata is entirely unknown. 



This genus, and that of Tremella, fo nearly approach each other, 

 that it is extremely difficult to afcertain their proper limits. The 

 original defign appears to have been, to confider fuch as were mem- 

 branaceous as C//W, and fuch as were gelatinous as TremelLr : but 

 this diftinction has been by no means adhered to; there being gela- 

 tinous Uha, and membranaceous Tremella:, to be met with in almoft 

 every author. Perhaps the bed diftinction would be, to confider 

 all thole which are membranaceous, and in which no vilible fructi- 

 fication exifts, as belonging to the genus Tremella ; and to arrange 

 thofe in which the fructification is known, and fuch as are filiform, 

 although without any perceptible fructification, with the Ulva. It 

 muft neverthelefs be evident, that fuch an arrangement would 

 entirely fubvert the genus Uha as it ftands in Sp. PL and very much 



Vol. III. H confufe 



MTSSOfJTtI 



BOTAWICAJ* 



GARDEN. 



