^n. 



evi'-lu:! liu C'jii'.; ,..!j.Cii i.auso (' ) guv.^.ogg'J. lo i:c 



fonned from the lo' er se^mentc oi' the apicLil cell ol' the 

 ricicr sporm' jiimu 



Tlie macrospor:un;_;;iiim mother cell divides by vl.IIg ^ '-: 

 ...-ive plane:-, vhich thus ToiTn li tetraliedreJ apical cell 

 between them (mL'.-^pp., Figs. 54, Hi). Tlie first all rorrri- 

 od as seen in a cross section of tlio capsule is 'TSiiall:- 

 toward the ventral side of the mother cell (Fig. ■'34). 

 Tliere is no rovndinr; Oxf of the mother colls from eacli 

 other in the sorus as described by Bftsgen ('30) pjid as 

 figured in Pilularia "by Moijnier (*S7), "br.t these abut 

 squiirely against each other (Figs. 53, 54-). The apical 

 cell of 'h.e nacrosporangium cu' s off tv/o somonts oneach 

 side wliicli foiT.i the lateral a.n.L basal ^alls of ir.e spo- 

 rangium and that part of the placenta or stalk v/liich. lies 

 between the sporangium and the region of viie plticental 

 "bundle (Fig. G2). Then a pericline is foj-med near 'iio 

 outer end of ho apical coll coi-a the archesporirm is thus 

 cut out ( arc. Fig. 62) and thie sponuigi um wall completd, 

 the fonner givin ; rise as Russov/ iias sho.vn to tlie tapetum 

 and spores. 



Wiile the macrosporangiii.: nas been developed thus, 

 there have boen impo -tant chc-^Jigos in tlie cells derivad 

 ^i'oi:i the microsporangivjn moihor colls .-.uid in the coll';; 'j- 

 section VI that are ousliin^; in between these. E; cii of 

 the four colls on ^'. ' -^ckens consideraijx ana 



