Ser. RHODOSPERMEiE. Fam. Rhodomelacecc. 



Plate XCI. 



HALODICTYON AUSTRALE, Haw. 



Gen. Char. Frond a tubular, simple or forked network, formed by 

 numerous, inosculating, confervoid jfilaments; the meshes irregular, 

 emitting at the angles free, horizontal ramelli. Fnictification : 1, 

 urceolate ceramidia, containing a tuft of pear-shaped spores ; 2, lan- 

 ceolate sticJiidia, containing a single or double row of tetraspores. — 

 Halodictyon [Zanard.), from aA,?, tJie sea, and Slktvov, a net. 



Frons (quasi ret'icidum tubulosiim, simplex v. furcaitirnj ex filis confervoideis 

 nmnerosis angidatim anastomosantibus confiata ; macidis irregidarihus, ra- 

 mellos Iiorizontales breves ad angulos emittentibus. Fruct. : 1, ceramidia 

 urceolata, fascicidum sporarum pyriformium includentia ; 2, stichidia lanceo- 

 lata, tetrasporas triamjide divisas tmi-biseriatas foventia. 



Halodictyon australe; network cylindrical, repeatedly forked, bristling 

 with excurrent, free ramuli; filaments capillary, the primary articula- 

 tions cylindrical, about four times as long as broad ; ceramidia pedi- 

 cellate, ovate-urceolate, with a prominent orifice. 

 H. australe ; reticulo terete dichotomo ramulis liberis excurrentibus furcaiis 

 dense velato ; filis capillaribus, articulis primariis cylindraceis diametro 4<-plo 

 longioribiis ; ceramidiis pedicellatis ovato-urceolatis, ore promimdo. 

 Hanowia austrahs, Sond. in Mold and Sch. Bot. Zeit. 1845, p. 52. PI. 

 Freiss. v. 2. p. 170. Harv. in Trans. R. I. Acad. v. 22. p. 558. Alg. 

 Austr. Fxsic. n. 115. 



Hab. Western Australia, Freiss ! Premantle, W. H. H., G. Clifton. 



Geogr. Distr. West coast of Australia. 



Descr. Fronds originating in a sponge-like, amorphous network of anastomosing 

 filaments ; several from the same base, cylindrical, 1-3 inches long, 2-3 

 lines in diameter, subsimple, or once, twice, or thrice forked. The cylin- 

 drical frond is formed of several parallel, longitudinal, branching filaments, 

 whose branchlets anastomose into the polygonal meshes of the tubular net- 

 work ; forming five- or six-sided meshes. From the angles of these meshes 

 are given off externally, short spreading or horizontal, free, once or twice 

 forked ramelli, which spread in all directions, and give the frond, to the 

 naked eye, a shaggy aspect. Tlie whole frond is pellucidly articulated and 

 composed of monosiphonous filaments ; the articulations of the meshes are 

 8-4 times as long as broad, those of the ramuli about the same, or shorter. 

 The ceramidia are borne on the free ramuli, the fertile ramulus being 

 shortened to a single joint ; tbey are somewhat inflated, with a projecting 

 oi-ifice; the spores are very narrow-pyriform, or rather clavate. The 

 colour is a clear red, discharged in fresh-water ; in drying it becomes darker 



