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body, which, is orginally curved round the 

 central vacuole. In the meantime, the proto- 

 plasm which is left, becomes differentiated 

 into two delicate fibrils, which attach them- 

 selves to the spiral nucleus at one end. The 

 vacuole, not unfrequently, as it is sur- 

 rounded by a delicate layer of protoplasm, 

 remains attached to the posterior end of the 

 Antherozoid. 

 (d) The sporangium bursts, and the spores fall 

 to the ground. From the commencement of 

 germination to the maturity of the anthero- 

 zoids there is an interval of about three 

 weeks. 



II. Megasporangia. 



Stages 1, 2, and 3 same as Microsporangia. 

 (4) One mother cell grows more strongly than the 

 rest ; it divides, and gives birth to four mega- 

 spores — again tetrahedrally shaped. The 

 megaspore is surrounded by a cuticularised 

 wall which is difficult to cut. All the other 

 mother cells remain undivided — their ultimate 

 fate is to be absorbed, though they exist in 

 some species for a considerable time. Germin- 

 ation begins to take place while the megaspore 

 is still IN THE Sporangium. 



(a) The protoplasm lying towards the corner 

 divides up and forms a delicate plate-like 

 cellular tissue, which afterwards produces 



