44 



But a common feature is, that no walls are present at the 

 base of the branches, these being always in open connection 

 with the mother cells. 



Regarding the cell-division, so far I have been able to see 

 in my material fixed in spirit only, this takes place by segrega- 

 tive cell-division in a very similar w^ay as I have found it in 

 e. g. Striwea, Chamaedoris etc., namely the plasma in a part of 



the fdament is at 

 once divided into 

 two or more parts 

 which again grow 

 together, being then 

 separated by a wall 

 (Fig. 28). 



For a long time 

 I had a suspiction 

 that the formation 

 of the wall was per- 

 formed in this way 

 but in spite of 

 much search I had 

 not been so fortun- 

 ate as to fmd it, 

 until in a not yet 

 examined collection 

 from St. Croix I was 

 so happy as to fmd 

 several filaments in 

 division. Of course, 

 in order to arrive at 

 any quite safe result 

 as to the cell-divi- 

 sion it would be of great help to examine living material 

 but still I think the process is carried out in the following way. 

 The filaments grow out to a certain length (Fig. 28 a, compare 

 also Figs. 26 and 27) and then the cell contents are simultane- 

 ously divided in several parts. Fig. 28 shows the development 

 as it takes place. In Fig. 28 a we have a long, not yet divi- 

 ded apical cell. In Figs. 28 6 and b\ the cell-contents are divi- 

 ded in some longer and shorter parts and these parts are sur- 

 rounded by a membrane. Finally in Fig. 28 c the cell-division 

 is fulfilled, the separate parts are grown together but now separated 



Fig. 29. Cladophoropsis membranacea (Ag.) Borgs. 



a and h, parts of filaments in which the cell con 



tents are more or less contracted to halls, c, trans 



verse section of a filament with 3 small cells, 



(About 30:1). 



