Plate XXXII. 



Fig. 143. LAURENCIA TENUISSIMA. 



Colour. Pale purplish or pinky-red; soon becoming yellow. 



Substance. Very tender; somewhat gelatinous,, though when fresh^ elastic. 



Character of Frond. Thread-like (filamentous); very slender; cylindrical; 

 much branched; tufted. Main stem generally undivided; bearing 

 numerous, alternate, spreading, wavy branches of unequal length; 

 some of the longest bearing a second series; and all set with nu- 

 merous, very short, slender, bristle-like, simple branchlets, which 

 taper finely to each end. 



Measurement. From 6 to 8 inches long; — of an inch in diameter! 



Fructification. Of two kinds. 1. Clustered spores in ovate, unstalked cap- 

 sules; external on the branchlets. 2. Tetraspores imbedded in the 

 fringing branchlets. 



Habitat. South of England and Ireland. Jersey. Isle of Wight. On rocks 

 between tide-marks; generally in shallow pools about half- tide level. 

 Yery rare. 



Slenderer than all the other Laurencias, and distinguishable from all by the 

 fact of its branchlets tapering finely at both extremities, though more especially 

 at their base. The figure does not give the bending delicacy of the real plant, 

 but the magnified portion is good. An old name has been given back to this 

 species: Chondria tenuissima. 



Fig. 144. LAURENCIA DASYPHYLLA. 



Colour. Pale-red or pink; sometimes tinged with brown; fading to yellow 

 or green. 



Substance. Somewhat gelatinous; soon decomposing. 



Character of Frond. Thread-like ( filamentous) ; slender; though not nearly 

 so much so as L. tenuissima; cylindrical; much branched; tufted. 

 Main stems generally undivided; bearing opposite or alternate branches; 

 the lowermost longest, and frequently bearing a second set; all set 

 with numerous short, club-shaped branchlets, tapering to the base, 

 but blunt at the tips (obtuse). 



Measurement. From 4 to 12 inches long. 



Fructification. Of two kinds. 1. Clustered spores in ovate capsides; external 

 on the lesser branches. 2. Tetraspores imbedded in the branchlets. 



Habitat. Shores of England and Ireland. On stones and shells in pools 

 near low-water mark, generally where the surface is covered with 

 sand or mud. Frequent. 



The blunt tips of the branchlets in this species distinguish it from L. tenu- 

 issima. Both are remarkable for being marked throughout, at short distances, 

 with lines across {transverse strioe). These are visible under a good pocket 

 lens in the younger parts of the frond; though but faintly, generally. It is 

 the internal structure showing through, which causes the appearance. This 

 p]ant is now called Chondria dasyphylla. 

 G3 



