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Practical Plant Biology. 



closely together, each with very thin cell-walls and completely 

 filled with protoplasm. The nucleus of each of these sperm- 

 mother-cells is elongated and continues to grow in length so that 

 it forms a short spiral thread in the outer part of the cell. At this 

 stage if water comes in contact with the antheridium, the swelling 

 up of the mucilaginous material in the base of the antheridium 

 expels the central mass of sperm-mother-cells, bursting open the 

 lid-cells of the antheridium. 



! Outside the antheridium the sperm-mother-cells continue their 

 development. The cytoplasm forms a coating over the elongated 



FIG. 27. Funaria hygrometrica, apex of male branch on left, and of a female 

 branch on the right, x 135. a, antheridium; b, sperms being set free ; 

 c, paraphysis ; d, leaf; e, neck of archegonium ; /, neck-canal; g, venter 

 of archegonium ; h, ovum. 



spiral i nucleus and is produced into two long cilia. By the 

 motions of these cilia, the sperms thus formed begin turning 

 round and round in the mother-cell. 



Archegonia are usually found at the apex of a shoot which is a 

 bifurcation of the branch which bears the male shoot. The leaves 

 round this apex are similar to the ordinary foliage leaves and 

 surround a number of paraphyses as well as the archegonia. 



The archegonia are in shape like tall narrow flasks on short 

 pedicels. The body is small and the neck long and narrow. 

 The ovum is contained within the body and the passage of the 



