Ser. RHODOSPERMEiE. Fam, Gelidiacea? 



Plate CXIII. 



THAMNOCLONIUM FLABELLIFORME, Sond. 



Gen. Chae. Frond dendroid or flabelliform, compressed or plane, imper- 

 fectly costate, rigidly horny or coriaceous, mostly covered with spi- 

 nous tubercles, composed of two strata ; the mediiUary stratum very 

 dense, of slender, cylindrical, longitudinally seriated cellules ; cortical 

 of roundish-angular, coloured cells. Fructification : \, cydocarps ?; 

 3, cruciate tetraspores, contained in nemathecia. — Thamnoclonium 

 {K'dtz.), from 6a^vo<i, a shrub, and kXqjv, a branch. 



Frons dendroidea v. fiabeUiformis, compressa v. plana, immerse costata, rigide 

 cornea et coriacea, scepissime spinuloso-verrucosa, stratis duohns composita ; 

 strata meduUari densissimo, celluUs cylindraceis (jracilibus longitudinaliier se- 

 riatis ; corticali ceUulis rotundato-angulatis coloratis formato. Fruct. : 1, 

 cystocarpia ignota ; 2, tetrasporce cruciatim divisce, in nemat/ieciis propriis 

 evolutce. 



Thamnoclonium fiabclliforme ; frond stipitate, flabelliform, entire or di- 

 vided, the lamina sponge-like, formed of closely interlaced, anastomos- 

 ing, rigid fibres. 



T. flabelliforme ; fronde stipitata flabelUformi iniegra v, partita, lamina spon- 

 gicsformi exfibrillis rigidis densissime intertextis anadomosantibusqiie consti- 

 tuta. 



Thamnoclonium flabelliforme, Sond. in LeJim. PI. Preiss. v. 2. p. 185. Harv. 

 in Trans. R. I. Acad. v. 22. p. 537. IIa?-v. Alg. Austr. Exsic. n. 153. 



Hab. Cast ashore near Fremantle, Preiss, Clifton, TF. H. H. 



Geogr. Distk. Western Australia. 



Descr. Root clasping, with 4-5 short, thick branches. Stem simple, or dividing 

 into several, 2-3 inches high, 2-5 lines in diameter, slightly compressed, 

 rigid and woody, compressed upwards, bifid or trifid, passing into the 

 base of a flabelliform lamina, through which it is continued as a more 

 or less evident, immersed, subdichotomous costa. This casta forms the 

 groundwork or axis of the fan-shaped lamina, and is sohd, and at first 

 naked, but it emits from its surface slender filiform processes, which soon 

 anastomose and cover it up in a reticulated stratum ; and also throws oft' 

 from its edges similar but much longer processes which, extend, inter- 

 weave, and anastomose, until a thick, sponge-like, fibro-cribrose body is 

 gradually formed. This sponge-like lamina is 5-10 inches long, 3-8 inches 

 wide, broadly obovate-cuneiform or subrotund, simple or divided into seve- 

 ral vertical lobes, fastigiate, with a rounded outhne. In old specimens 

 small fruit-leaves {sparapliylld) are irregularly emitted from the surface of 

 the spongy network; these are 2-4 hues long, flabelliform, bifid or twice 

 forked, and perfectly glabrous, and they bear in their upper half roundish 



