Ser. Melanospermk^. Fain. Dictyotaceoi. 



Plate CLXXXVI. 



DICTYOTA N/EYOSA, Suhr. 



Gen. Char. Root woolly. Frond flat, linear, membranous, ribless, areo- 

 late, dichotomous or irregularly cleft. Fructification : spores super- 

 ficial, either collected in spot-like sori or scattered singly over both 

 surfaces of the frond. — Dictyota {Lamo7ir.), from Siktvov, a net ; 

 because the surface, under a lens, has a netted, or, rather, a tessellated 

 appearance. 



Radix stuposa. Frons plana, linearis, membranacea, ecostata, ureolata, dichotoma 

 aid va(jefissa. Frtict. : sporce superji dales, in soros maculaformes ac/gregatce 

 V. singulatim per utramque paginam frondis dispersce. 



Dictyota navosa ; frond decompound-dichotomous, segments elongate, 

 broadly-linear, quite entire, obtuse or subacute ; areolae square ; spores 

 in oval-oblong or linear spot-like sori, scattered over the whole sur- 

 face of the frond. 



D. ua^vosa ; fronde decomposito-dicJiotoma ; segmentis elongatis lato-lhiearihiis 

 margine integerrimis obtusis v. acuthisculis ; areolis subquadraiicis ; sports in 

 soros macidaformes ovaU-oblongos linearesve per totam supcrjiciem sparsos 

 collectis. 



Dictyota nfevosa, Siilir, in Flor. 1834, t. 1./. 4. /. Ag. Sp. Alg. v.l. p. 95. 

 Harv. Alg. Austr. Exsic. n. 74; Fl. Tasm. v. 2. p. 291. 



Dictyota Pappeana, Knlz. Sp. Alg. p. 557. 



Hab. Georgetown, Tasmania, fF. H. H. 



Geogb. Distk. Cape of Good Hope. Tasmania, 



Desce. Root (of the Tasmanian specimens) not seen. Frond 12-18 inches 

 long, very much divided, nearly regularly dicliotoraous, the segments about 

 half an inch broad, or rather broader, linear, Hat or slightly undulating, 

 quite entire at the margin, with narrow and subacute axils, very erect, 

 sometimes tapering at the extremity to a bluntish point, sometimes rounded 

 or emarginate at the apex. Sori very abundant, thickly scattered over the 

 whole frond, oblong or linear, extending longitudinally. Colour a pale 

 greenish-olive, or darker, varying with the age of the specimen. Substance 

 when young membranous and thin, afterwards thicker. When young, the 

 frond adheres to paper in drying. 



I venture to refer the specimens, one of which is here figured, 

 to the I). iKBvosa of Von Suhr, described originally from Cape 



