Fertilisation in Cryptogams 173 



But the nucleus must be from both. The facts to be dis- 

 cussed in the two following Sections, teach us that, in 

 fertilization proper, the other organs come from the 

 mother only. But this is simply to be regarded as a spe- 

 cial adaptation. 



The chromatophores of the other Zygosporese, exam- 

 ined with this end in view, behave essentially similarly to 

 those of Spirogyra. They touch one another (Epithe- 

 mia), or do not unite (Zygnema and many others), but 

 they never conjugate in the true sense of the word.^ At 

 the first divisions of the zygospore, the paternal and ma- 

 ternal chlorophyll grains must therefore always be dis- 

 tributed to the individual cells of the thread. 



Schmitz, who was probably the first to observe the 

 conjugation of the nuclei in the Zygosporese, and who 

 studied carefully the above mentioned behavior of the 

 chromatophores, demonstrated in a clear manner that, in 

 these cases also "the essential point is only the union of 

 the nucleus of the male cell with the nucleus of the female 

 cell."^ And the facts which have been discovered later 

 have fullv confirmed this statement. 



J. Fcrtilizatioii in Cryptogams 



Schmitz, in his important monograph on the chro- 

 matophores of the algae, has comprehensively demon- 

 strated that these structures which, at each vegetative 

 cell-division, are transmitted from the mother-cell to its 

 daughter-cells, are usually entirely lacking in the sper- 

 matozoids.^^ The egg-cells, however, always possess these 



^Schmitz. Die Chromatophoren der Algen, p. 128. See also 

 Overton and Klebahn, loc. cit. 

 ^Loc. cit. p. 128. note 2. 

 loSchmitz, loc. cit. p. 120 ff. 



