270 F. liORGESEN 



in diameter; the colour is denser and more deeply red than in the sterile cells, 

 and no chromatophore could be distinguished. 



The dried plant has a fine rose colour. 



Area of distribution: Endemic. 



E. Laurenciae nov. spec. — Fig. 16. 



Thallus suborbicularis, e filamentis irregulariter radiantibus et ramosis 

 compositus, in circuitu thalli inter se liberis, in media parte plus minus con- 

 natis. Ramificatio aut alterna, aut secunda sat irregularis. 



Cellulae oblongae-subcylindricae, 4 — 5 (x latae et 8 — 10— 12 \>< longae. 



Fig. 16. Erythrocladia Laurenciae nov. spec. Parts of thallus; in a the tissue of the host is 



visible. C. 400 /,. 



In the thick epidermal walls of Laurencia claviformis another representative 

 of the genus Erythrocladia was found. 



The plant has long ramose filaments with apical growth and these fila- 

 ments radiate from the centre in all directions covering a more or less extensive 

 area, probably as much as I mm across. 



The ramification is rather irregular, lateral or alternate. In some specimens 

 it happens that the alternate branching is so regular that the branch with its 

 branchlets gets a pennate appearance. In the centre of the plant the filaments 

 gradually combine to form a more or less coherent layer (Fig. 16 a). 



The cells are oblong-subcylindrical, often a little curved so that the fila- 

 ments get sinuated; cells 4 — 5 ;j, wide and generally 2 — 2 V2 times as long. 

 In the older parts of the thallus the cells get proportionally shorter and thicker, 

 8 — 10 (j. wide and about as long or a little more. They contain an irregularly 

 lobed parietal chromatophore with one or sometimes two pyrenoids. 



In some instances a roundish cell were found cut off from mother cell 

 by an oblique wall. Such cells having more dense and homogeneous contents 



