4 Elizabeth Acton. 
these shoots are relatively long and thin but they all contain a 
chloroplast. 
Fig. 3. A, small individual shewing change of polarity as described in 
text ; B, branches modified as “ cirrhoids” (c) ; C, “ rhizoid ” (r) formed from 
apical cell of branch ; D, shoot illustrating the thickening of the cell wall at 
points where new branches are about to appear. A, B and D x 62 ; C x 96. 
“ Indifferent ” branches are long thin shoots poor in chlorophyll 
which originally have no definite function but can develop, accord- 
