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to the cell-wall of the branch nearest above. Most of the apices 

 of the top cells touch the branches above even before the tena- 

 culum has grown out and this need only be quite short, but 

 sometimes it happens that it does not succeed in coming into 

 close connection with another branch and then it can grow rather 

 long like a rhizoid (fig. \kf). To begin with it is only the top 

 cell of each branch which fixes itself in this way, forming a kind 

 of edge along the side of the frond, but later on in the older 

 frond nearly all the side branches of the second, third and higher 

 order are provided with tenacula at the top and fastened to other- 

 branches (fig. 14 d). In this way, in good accordance with what is 

 well-known in other Struvea-specles, all the branches, loose at first, 

 form a connected whole. Sometimes, but more seldom, I have 

 found two tenacula growing out from the same top of the cell. 



In the frond the lowest cell in the midrib is considerably lar- 

 ger (about 3 times) than the other cells in it, as is the case also 

 in Struvea anastomosans. 



With regard to the cell-wall this is rather thick in the lowest 

 part of the stalk, growing thinner upwards and in the frond. The 

 wall shows longitudinal and transverse striations, as is also men- 

 tioned by Murray and Boodle (I.e. p. 271) for Struvea plumosa. 



As to the wall plasma and its contents this is very like what 

 we find in Valonia. The chromatophores (fig. 14 g) are plate-shaped, 

 of irregular polygonal form, often with elongated angles forming in 

 this way a net-work. In each chromatophore a rather large pyre- 

 noid is nearly always present. Behind the chromatophores we 

 find the numerous nuclei rather regularly distributed. 



The whole plant with stem and frond together reaches a 

 height of about 10 cm, the length of the frond may measure up to 

 4 cm and the breadth 2V2 cm. The stalk is normally unbranched 

 but a single specimen was found having a side-branch also crowned 

 with a frond. 



This species seems to be nearly related to Struvea anastomo- 

 sans by its large basal cell in the frond and by the mode of rami- 

 fication, but this is much more regularly distichous, the frond has 

 another form, is longer, containing several, more opposite pairs of 

 branches, the top cells in the branches of the first order are longer 

 etc. ; furthermore, the stem has a number of annular constrictions 

 at its base, which is not the case in Struvea anastomosans and 

 finally, the size of our plant is much larger. 



