APICAL FORMATION OF CILIA AND ASSOCIATED BRANCHING OF THE AXIS IN THELICHEN TELOSCHISTES-FLAVICANS

The origin of cilia at branch apices and the concomitant bifurcation o f the apex in the lichen Teloschistes flavicans were investigated with optical and scanning electron microscopy (SEM). Cilia are determinate structures formed continually from superficial mycobiontic cells that extend jointly from the recurved surface of the apical growth zone. I nitiation of the cilium centrally results in bifurcation of the axis t o both sides of the cilium primordium. The general organogenetic featu res of the growing apices of T. flavicans are compared with those of h igher plant shoot apices.