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of its component cells", I think that Harvey has most probably 

 observed some older stages of divided cells and as often only four 

 cells are the result of the division (cfr. my fig. 5 a) he has made it 

 a quadrisection. 



As to Askenasy's description of the cell division, the cells 

 being divided into two—three layers of cells, this as already men- 

 tioned seems to allude to a species different from Diet, favulosa. 

 And when Askenasy tells us further, that the space over and 

 under the cross wall between the large cells is filled with small 

 cells, this also is not quite correct, this space being filled up with 

 the hapteræ growing out from the small cells. 



As to Schmitz' opinion that our plant can be compared 

 with a Cladophora with large cells I may point out, as already 

 mentioned above, that I have never found a trace of such a like- 

 ness; on the other hand, young plants yet massive can be very 

 like a Valonia. Our plant may also be referred to the Valoniaceæ 

 and not to the Gladophoraceæ, as Oltmanns does on the autho- 

 rity of Schmitz. And when Miss Crosby compares our plant 

 with a Struvea this is quite as misleading as when Schmitz 

 compares it with a Cladophora. 



I consider Dictyosphœria favulosa as very nearly related to 

 Valonia; the form of Valonia utricularis (Roth) Ag. I have figured 

 (fig. 3) shows a striking likeness, also having along the edges of 

 the cells a row of small lentiform cells from which rhizoids grow out 

 and fix themselves to the neighbouring cells. I therefore quite agree 

 with Murray, who considers our plant as "one of the simplest 

 forms of valonioid organism", when he gives the following descrip- 

 tion of it: "In Dictyosphœria favulosa we have simply an aggre- 

 gate of similar cells not forming a definite frond, but cohering in 

 an unbranched mass, this colony of units being held together 

 solely by tenacula". 



The remarkable method of cell division, the cell contents 

 being transformed to a number of balls, reminds one very much 

 of the process of cell division in Siphonocladus tropicus as described 

 by me. And the cell division of Struvea as described in this 

 paper is also very similar, and likewise that found in the apex of 

 the stalk of Chamœdoris. 



Upon the whole, this "ball-cell-division", reminding so very 

 much on the free cell-division, has shown itself characteristic of 

 many Valoniaceæ. 



