^72 BOTANICAL GAZETTE ' [m.4RCH 



PLATE VI 



Mitosis in the vegetative cells of the prothallium 



Fig. I. Prophase; nucleus with a continuous spirem. 



Fig. 2. The nucleus after segmentation of spirem into a nu 

 somes, most of them before the s+»"^^ ^^ i.^r»m'H, ^tr^oi ^^lu*-:^^. 

 caps with a few fibers are present 



two 



Fig, 3. The nucleus after disappearance of membrane: chromosomes which 



arraneed Darallel to the axis 



passing between the two pol 



Fig. 4. Late prophase; daughter halves of chromosomes are in close contact 



with each other; 



!gul 



an equatorial plate; the vertical arms of the L's are directed to the poles 



horizontal arms are lying 



arms appear like dots. 



gularly radiating arrangement 



fig. 4; the horizontal arms 



ase 



Fig. 9 



anaphase; tNo sets of daughter chromosomes near the pole, 

 ' telophase; daughter chromosomes regularly arranged at pole 



present. 



•wn in the previous figu 



two 



It of chromatin substance in daughter nuclei showing polarity. 



Spermatogenesis 

 Fig. II. Telonhase preceding formation of spermatid mother cells 



spermatid mother ceUs just organized : two 



pol 



H 



Still later stage than that in pg. 12; arrangement of chromatin material 

 polarity. 



More advanced stage than that shown in jig. 13 ; nucleus of sper- 

 abnost in resting stage; no polarity in distribution of chromatin 



two kinoplasmic 



material; two blepharoplasts mthin atoplasm on opposite 



i-iG. IS. Nudeus of spermatid mother ce 

 caps with a few fibers ; blepharoplast near pol 



IG. 16. Spirem segmented into chromosomes; nuclear membrane begins 

 to d^ppear at poles of nudeus; blephaix)plast near the pole. 



IG. 17. Late prophase; nudear membrane has completely disappeared; 

 Chromosomes split longitudinally; blepharoplast near center of spindle. 

 the Jes^ ^^Ptase; two sets of daughter chromosomes on the way toward 



Fig. 19. Early telophase; daughter chromosomes grouped at pole with regular 

 arrangement; blepharoplast retains same position as befo^ ' 



