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PLANT MORPHOLOGY 



Fig. 151. Porella bolanderi. A, dorsal view of gametophyte with nearly mature sporo- 

 phyte, X30; B, ventral view of same, showing row of reduced ventral leaves and dorsal 

 leaves with small ventral lobes; C, horizontal longitudinal section of tip of gametophyte, 

 showing apical cell and developing leaves, X400; D, longitudinal section of antheridium, 

 X250; E, longitudinal section of nearly mature archegonium, showing egg, ventral canal 

 cell, and eight neck canal cells, X400. 



Sex Organs. The antheridia and archegonia may occur on the same 

 plant or on separate plants, depending on the species. They are never 

 sunken in the tissues of the gametophyte. The antheridia arise in the 

 leaf axils, very commonly in groups of two to four; but sometimes they 

 are solitary, as in Porella, or in groups of more than four. Often the 

 antheridia are accompanied by paraphyses. In Lophozia, Nardia, and 



