292 FLORA OF TASMANIA. [ Alga, by W. H. Harvey. 
Var. 8; fronde simpliciuscula intestineformi.—Harv. Alg. Eesic. n. 89. 
Has. Georgetown, R. Gunn, W. H. H. 
Distris. South coasts of New Holland. 
Frond 6 inches to a foot or more in height, from 2—4 lines in diameter, or sometimes upwards of half an inch 
across the swollen branches, very irregular in ramification, sometimes nearly simple, sometimes much branched. In 
the simpler varieties the branches are often much swollen. The substance is firmly carnoso-gelatinous and tough, 
and the colour a dark-brown, becoming blackish when dry. The axial filaments are very dense, those of the peri- 
phery remarkably slender, elongated, several times dichotomous, and perfectly cylindrical, their joints three or four 
times as long as broad. The spores are obovate, with a wide perisperm, and are borne near the bases of the peri- 
pheric filaments.—We are not sure whether this species be correctly referable to Liebmannia, where we place it on 
account of the dense axis. 
Gen. XXIX. MESOGLOIA, 4g. 
(J. Ag. Sp. Alg. i. p. 56. Kütz. Sp. Alg. p. 544. Harv. Phyc. Brit. t. 31, 82.) 
1. Mesogloia virescens (Carm.; Harv. Phyc. Brit. t. 82; J. Ag. Sp. Alg. i. p. 56). 
Has. Georgetown, R. Gunn. 
Disrmrg. Atlantic shores of Europe, Gulf of Mexico, south coast of New Holland, and at the Friendly 
. Islands. (Vavau, W. H. H.) . 
Gen. XXX, CLADOSIPHON, Katz 
(Kütz. Phyc. Gen. p. 329. t. 25. f.1. J. Ag. Sp. Alg. i.p. 54. Kütz. Sp. Alg. p. 547.) 
l. Cladosiphon Chordaria (Harv.) ; caule indiviso percurrente, ramis lateralibus longissimis guo- 
quoversis simplicibus v. subdichotomis, ramulis paucis, axillis obtusis, filis peripherieis simplicibus brevis- 
simis clavatis unicellularibus, sporis ellipticis.—Harv. Alg. Exsie. n. 95, 96; Phyc. Austr. t. 60. 
Var. B. Dictyosiphon ; fronde minori densius ramosa, ramis ramulis plus minus obsitis.—C. Dictyo- 
siphon, Harv. Alg. Exsie. n. 97. 
Has. Georgetown. 
DisrniB. South coast of Australia. 
_ Frond a foot or more in height, and as much in the expansion of the branches. Stem mostly simple, densely 
clothed throughout with long lateral branches which issue in all directions. Branches filiform, varying in diameter 
from the thickness of a hog’s-bristle to a line; in the former case of equal diameter throughout, in the latter taper- 
ing at each end, simple and bare of ramuli, or once or twice forked, or, in var. ß, furnished with numerous short 
patent ramuli. In young specimens the central cavity is narrow, in more advanced it gradually widens, the frond 
becoming somewhat inflated. The walls of the tube are composed of several rows of longitudinal filaments, densely 
aggregated into a firmly cellular flesh; the periphery is formed of minute, radiating, simple filaments, each formed 
of a single clavate cell, issuing from the cells of the outer row of those composing the tube-wall. Zlliptical spores 
nestle among the filaments of the periphery.— The Georgetown specimens are of much greater diameter than those 
from Port Phillip, on which the species was founded. This seems to arise from an increase in diameter of the cen- 
tral tube. T cannot detect any difference in microscopic character, and therefore have brought them together, and 
also reduce to the same my C. Dictyosiphon, which, from its difference in habit, I had previously distributed as 
distinct. , 
i a Cladosiphon nigricans (Harv.); fronde filiformi longissima subsimplici v. parum ramosa, ramis 
lateralibus paucis vermiformibus elongatis nudis v. ramulos paueissimos ferentibus, tubo frondis demum 
amplo, filis peripherieis fasciculato-ramosis longiuseulis articulatis, articulis diametro sesquilongioribus 
terminali globoso.—Harv. Alg. Exsic. n. 94. 
