34 



ance and mode of foriii&-tion to a rhizoid. The cavity of 

 the outgrowth is perfectly contimious with tjie cavity of 

 tlie cell froifl which it originates (fig. 51). A similar 

 tube grows up more slowly from t}ie cell helow and the two 

 meet near the centre of the old cell cavity (fig. 52). 

 They fuse at their tips (fig. S3) to form a continuous hol- 

 low cylinder; the cylinder increases in size and comes to 

 replace the dead cell exactly. The usual intercellular con 

 nection is formed at the junction of the nev/ cell witli each 

 of the t\.o old cells v/hich contributed to its formation. 

 A similar process of regeneration was described for Grif- 

 fithsia Coral lina by JA1ICZEV7SKI ('76), with this difference 

 ho'.vever, that in G, C orallina only the cell above txie dead 

 cell plays a part in the formation of tlie new cell. TOBLER 

 ('03) has shown that a simil&.r process takes place in oth- 

 er species of Griffithsi a and in Bornetia . 



This process leads at times to the production of a cell 

 of very peculiar appearance. When the cell next belov/ tv^o 

 branches perishes, the lowest member of each branch puts 

 out a tube (fig. 51) which meets tlie tube from the cell be- 

 low. The tliree fuse at the point of contact and a Y-shaped 

 cell results, which is a product of tlie fusion of three dis^ 

 tinct cells (fig. 54) . 



