306 FLORA OF TASMANIA. [Alge, by W. H. Harvey. 
tenuissima percursa vel omnino ecostata lineari plana decomposite pinnata, pinnis pinnulisgue alternis 
patentibus axillis rotundatis, ultimis oblongis obtusis simplicibus v. pauce dentatis, ceramidiis loteralibus, 
axillaribus vel terminalibus nunc fasciculatis globoso-inflatis longiuscule pedicellatis.—Harv. Alg. Ezsic. 
n. 944. (Tas. CXC. A.) ; 
Has. Georgetown, rare, R. Gunn, W. H. H. Southport, C. Stuart. 
Disrris. South coast of Australia. 
Frond a foot or more in length, and as much in expansion, about a line or a line and a half in breadth in all 
parts, furnished for some inches above the base with a thick cartilaginous midrib, which is gradually dissipated * 
upwards, the upper half of the frond being ribless, and quite flat, but traversed by a very slender, internal, medial 
vein, which is not always visible, though strongly marked in the broader and more luxuriant specimens. The rami- 
fication is distichous, and about thrice pinnate; the primary branches or pinne elongate, few and distant; the 
secondary 1-2 inches long, about half an inch asunder, and regularly alternating ; the tertiary short, with .one or 
two tooth-like incisions. All the ranches and their divisions are remarkably patent, with rounded angles. The 
apices are blunt, and frequently as if truncate. The ceramidia are as large as mustard-seeds, globose, on stalks as 
long as, or longer than themselves, and are very irregularly distributed over the frond, being sometimes terminal, 
sometimes on the sides of the smaller ramuli, sometimes in the axils, and sometimes actually fasciculate on different 
parts. Their walls are very thick, and they contain a large tuft of clavato-pyriform spores. The colour of the 
frond is of a deep clear red, similar to that of many Plocamia.—Mr. Stuart’s specimens from Southport are broader 
than that represented in our figure, and the frond is everywhere traversed by a slender medial vein, which we do not 
find obvious in the Georgetown plant. It is possible we may confound two species ; but as their vein is less 
strongly marked in some individuals than in others from the same locality, we think perhaps it may exist in all, but 
from some fault in the drying may have been obliterated.—PrATE CXC. 4. Fig. 1, Ptilonia australasica, nat. size ; 
2, a fragment, with a pedicellate ceramidium ; 3, tuft of spores from the same; 4, some spores separated :—the latter 
figures more or less highly magnified. 
Gen. LV. CLADHYMENIA, Harv. 
(Hook. and Harv. Alg. N. Zeal. in Lond. Journ. Bot. iv. p. 54. Harv. Ner. Austr. p. 87. Kütz. Sp. Alg. 
p. 879. J. Ag. Sp. Alg.ii. p. 771.) 
1. Cladhymenia conferta.—Dictymenia conferta, Harv. Ner. Austr. p. 29. t. 8. Delesseria con- 
ferta, Ag. Sp. Alg. 1. p. 177. Fucus confertus, R. Br. in Turn. Hist. t. 184. 
Var. B. foliifera ; ramis folia lanceolata tenui-membranacea ex margine apicibusque emittentibus. 
Has. Georgetown, R. Gunn, W. H. H. Var. B. Southport, C. Stuart. 
DisrRrB. South coasts of New Holland. 
During my recent visit to Australia, I ascertained the tetrasporic fruit of this plant, and am thereby compelled 
to remove it from Dictymenia to the present genus. The tetraspores form marginal sori, continued for some dis- 
tance along the edge of the frond. Var. / is a remarkable variety, resembling at first sight some states of Delesseria 
hypoglossum. It is connected with the common form by specimens of intermediate character. 
Gen. LVI. LAURENCIA, Lamour. 
(Lamour. Ess. p. 42. Grev. Alg. Brit. p. 108. Harv. Ner. Austr. p. 81. J. Ag. Sp. Alg. ii. p. 740.) 
l. Laurencia Forsteri (Grev.; Harv. Ner. Austr. p. 85; J. Ag. Sp. Alg. ii. p. 744).—Fucus 
Forsteri, Turn. Hist. t. 77. 
Has. On Zostera, etc., common. 
Disrris. All along the coasts of New Holland. 
