Ser. RHODOSPERMEiE. Fam. Ceramiacecs, 



Plate LXXL 



PTILOTA STRIATA, Haw. 



Gen. Char. Frond compressed or two-edged, distichous, pectinato-pin- 

 nate, inarticulate, with an articulate monosiphonous axis ; the pin- 

 nules sometimes articulate. Fructification : 1, involucrate favellce, 

 containing numerous angular spores ; 2, tetraspores attached to the 

 pinnules, sessile or stalked, solitary or glomerulate, tripartite. — 

 Ptilota (4^.), from tttiXwto^, pinnated. 



Frons compresm v. anceps, disticJia, pect'mato-pinnata, corticata, axi artictdato 

 monosiphonio percursa ; pinnulis scepius corticatis, nunc pellucide ai'ticulatis. 

 Fruct. : 1, favellce irwolucratce sporas numerosas angulatas foventes ; 2, teti'a- 

 sporce ad pinmdas sessiles v. pedicellatee, sparsce v. glomerulatce, triangule 

 divisce. 



Ptilota striata; frond slender, two-edged, alternately decompound; 

 branches and their divisions subdistant, rod-like, transversely rugu- 

 lose, closely pectinato-pinnate ; pinnules alternate, subulate, inarticu- 

 late, transversely striate ; favellse borne on the inner edge of the pin- 

 nules, below the apex ; the involucre formed of many slender, invo- 

 lute, articulated filaments ; tetraspores on branching, confervoid pedi- 

 cels, developed along the edges of the pinnules. 



P. striata ; fronde angusta ancipiti alterne pluries decomposita ; ramis majoribus 

 minoribusque sparsis virgatis transversim rugulods crebre peciinato-pinnatis ; 

 pinnulis alternis subidatis inarticulatis transversim striatis ; favelUs ad mar- 

 ginem superiorem pbimdarum infra apicem sessilibus; involucro ex fills niimero- 

 sissimis articulatis involventibus forniato ; tetrasporarum pedicellis ramosis 

 articulatis ad margines pinnidarum evolutis. 



Ptilota striata, Harv, Alg. Austr. Fxsic. n. 477. 



Hab. Cast ashore from deep water, Eottnest Island, near Premantle, 

 r. H. H. 



Geogr. Dist. Western Australia. 



Desck. Root a large, flattened disc, quarter to half an inch in diameter. Fronds 

 tufted or soUtary, 6-12 inches long, and as much in the spread of the 

 branches, half a line in breadth, compressed and sharply two-edged, decom- 

 pouudly branched in an irregularly alternate manner, the general outhne 

 being somewhat flabeUiform and fastigiate. Branches three or four times 

 alternately decompound, the divisions erecto-patent, issuing at acute angles, 

 subdistant, of unequal lengths, and unequally compound. All the branches 

 and their divisions are closely pinnulated with minute, alternate, subulate 

 pinnules, one to two lines in length. Under a pocket-lens the branches 

 and their divisions appear transversely furrowed at distances of about half 



