Ser. RnoDOSPERMEiE. Fam. Ceramiacea. 



Plate CCXVIII. 



CALLITHAMNION LARICINUM, Harv. 



Gen. Char. Frond filiform, branched, articulated, monosiplionous, the stem 

 and branches (in many species) at length thickened internally, or 

 coated externally with decurrent filaments; ramuli always pellucidly 

 articulate and monosiphonous. Fructification : 1, favellce, generally 

 in pairs, axillary or sessile on the branches, naked, containing nume- 

 rous angular spores ; 2, tetraspores naked, sessile or pedicellate, dis- 

 tributed on the ramuli, generally triangularly parted. — Callith amnion 

 {Lyngb.), from KoXKa, beautiful, and Oa/ivtov, a little sJiruh, 



Frons filiformis, ramosa, articidata, nionosiphonia, caule ramisque majorihus 

 (in pluribus), demumfibris decurrentihus interne vel externe evolutis corticatis 

 v.firmatis; raviulis semper pellucide artlctclatis. Fruct.: \, favella biuatte, 

 axillares v. ad ramos sessiles, n?id(e, sporas numei'osas angulatas foveutes ; 2, 

 tetraspoi'a nudce, ad ramulos sessiles v. pedicellatce, triangule v. cruciatim di- 

 viscB. 



Callithamnion laricinum; frond cartilaginous, setaceous (1-8 inches 

 high), opaque nearly to the ends of the branches, pyramidal in out- 

 line, branched toward every side ; branches alternate, patent, gra- 

 dually shorter upwards, everywhere beset with dichotomo-multifid 

 ramuli ; ramuli several times forked, the segments spreading, the tips 

 very short and spine-like ; favellse in pairs, oblong, simple or forked ; 

 tetraspores globose, scattered on the sides of the branchlets. 



C. laricinum; fronde cartilaginea setacea ("i-S-uncialiJ fere ad apices ramorum 

 corticata glabra quoquoversum ramosa ambitu pyramidali ; ramis alternis 

 patentibus superne sensim brevioi'ibus, ramulis dicJiotomo-multifidis undique 

 obsessis, ramuloriim segmentis patentibus ultimis brevissimis spinceformibus ; 

 favellis geminis oblongis simplicibus v. furcatis ; tetrasporis globosis ad latera 

 ramulorum sparsis. 



Callithamnion laricinum, Harv. in Trans. R. I. Acad. v. 22. p. 562; Alg. 

 Austr. Exsic. n. 510. Harv. in Hook. Fl. Tasm. v. 2. p. 335. 



Hab. On Zostera, at Rottnest, W. H. II. Garden Island, G. Clifton. 

 Port Fairy, W. H. H. Warnambool, H. Watts. Port Arthur, Tas- 

 mania, JF. H. H. 



Geogr. Distr. West and south coasts of Australia. Tasmania. 



Descr. Root a small disc. Fronds subsolitary, setaceous or ultra-setaceous, 

 from 2-8 inches high, with an undivided leading stem closely set with 

 lateral, alternate, virgate branches, which are either simple or pinnate ; the 



