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BOTANY 



PART II 



At the apex of the embryo-sac are found the archegonia, usually four 

 in number, and separated from one another by some layers of cells. 



Fie. 540. Dioon edule. Upper portion of the nuceilus at the period of fertilisation. The pollen- 

 tubes have grown down from the pollen-chamber through the nuceilus after becoming 

 attached by lateral outgrowths. They have reached the archegonial chamber and two of 

 them have already liberated their contents. Two large archegonia with projecting neck-cells 

 are present. (After CHAMBERLAIN.) 



Each archegonium has a neck, and ultimately cuts off a canal-cell. 

 The archegonia are situated at the base of a depression in the pro- 



