Handbook of Plant and Crop Physiology

810 WALLACE

Figure 4 Caulonemal filaments from a 3-week-old culture of Physcomitrella patens, which has grown un-
der standard conditions. The main filament axes are composed of caulonemal cells. Almost every subapical
caulonemal cell has divided to produce one or more side branches. Most of these have developed into filaments
of secondary chloronema. A few have produced buds, which may be seen at various stages of development. Bar
1 mm. (From Ref. 3.)