27 



grows for a time more rapidly than the main filament, until 

 it ahout equals it in size. Thus an apparent, or false, 

 dichotomy results. True dichotomy'' appears never to occur, 

 as in no case has a braiTidh ke.^ foxind to divide longitudinal- 

 ly. Frequently more than one "branch is laid dovm at a node 

 so that trichotomy results, and in the larger cells near 

 the oase of the plant, four branches have been observed to 

 proceed from the suminit of the same cell, 



A second laethod of cell division occurs commonly in 

 the apical cells of the smaller branches, and sometimes in 

 the division of the larger cells below the apex. A ring of 

 cellulose projects inward from the cell wall a short dis- 

 tance from the apeii, very much as was described for Cladoph - 

 ora oy Strasburger {'88), (figs. 43,44). The ring grows in- 

 v/ard, but not so as to cut off the new cell completely. An 

 open circular pore is left in the center, across which the 

 protoplasioic plugs are soon formed in the usual v/ay. ITo 

 pit-closing membrane is formed between cells separated in 

 this manner. 



The second mctliod of division, which is the usual one 

 in coenocytes, differs from the first in that the daughter 

 cell is from tjie beginning mud. more nearly equal in size 

 to the cell fro.'.i which it is cu.t tlian is the case in the 



