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STRUCTURAL BOTANY 



within its mother-cell is precisely similar to the same 

 process in Liverworts or Vascular Cryptogams. The 

 antheridia open on access of water ; the cells of the 

 wall swell and press upon the mother-cells within, 

 which are expelled, when the top of the sac ruptures, 

 in a single mass. The mucilaginous cell-walls of the 



Fio. 61. Longitudinal section through the apical bud of a 

 male shoot of Funaria. d, leaves cut through the midrib ; 

 e, leaves cut through the lamina ; c, paraphyses ; several 

 antheridia are shown ; a, very young ; b, nearly ripe 

 antheridium. Magnified 300. (After Sachs. ) 



mother-cells disappear and the spermatozoids are set 

 free ; each has a spirally curved body and two cilia, 

 just as in the Liverworts (see Fig. 62, C). The 

 antheridia are accompanied by multicellular hairs with 

 large heads, called the parapliyses. Their function is 

 probably to secrete water, and so to ensure sufficient 

 moisture for the development of the antheridia. 



