m 



THE jungermanniAles 



Fig. 42. — A, Vertical, B, C, horizontal sections through the apex of Pallavicinia 

 cylindrica; *, apical cell, A, X22S; B, C, X430; D, E, Pellia epiphylla; D, ver- 

 tical section; E, horizontal (optical) section, X450. 



