89 



Fig. X. — ^'Section of an oogonium in which the peripheral nuclei have 

 divided up into a number of smaller nuclei, n^. The wall o 

 the oosphere, o, is just beginning to form, and appears as a 

 somewhat granular layer, just inside the layer of periplasm, 

 p. The nuclei of the antheridium, a, have also divided up 

 in the same manner; b, antheridial tube. A single nucleus, 

 n, is seen in the protoplasm of the oosphere, x about 

 1,000; Swifts y'^ water-immersion. 



Fig. XI. — Section of an oogonium and antheridium, showing fertilising 

 tube containing two nuclei. x 1,000. 



Fig. XII. — Section of an oogonium and antheridium after fertilisation is 

 supposed to have taken place. The fertilising tube is seen to 

 open into the oosphere by a small hole, /, placed very near 

 the end of its swollen portion. The antheridium contains a 

 number of nuclei, and the oospore, o, contains two very 

 faintly stained nuclei, n. x 1,000. 



I 



