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Scientific Proceedings, Royal Dullin Soeieiy. 



between the oospore and oogonial walls before it finds its exit through 

 the latter, which may be a considerable distance from the point of origin of 

 the germ-tube. A comparatively simple case of this kind is illustrated in text 

 fio-. 2, below. 



Fig. 1. Sexual organs containing an oospore, the stages of germination of 

 which were watched in a hanging drop. At the outset the spore, which 

 practically filled the spherical part of the oogonium, was provided with 

 the normal thick wall and contents similar to those shown in Plate XIII, 

 fig. 1. At the time of the production of the germ-tube, when the figure 

 was drawn, this wall had become so thin as to be practically invisible. 

 The germ-tube emerges through the oogonium wall at a point very 

 slightly below the plane in which the drawing was made, x 510. 



Fig. 2. Another set of sexual organs in which the stages of germination were 

 followed in a hanging drop. Here the originally thick-walled oospore 

 did not fill the oogonium. The germ-tube originates on the surface 

 of the now thin-walled oospore, somewhat to the right of the centre, 

 and penetrates the oogonium wall after traversing some distance in 

 the space between the oospore and oogonium walls. Previous to 

 penetration it becomes considerably swollen, x 510. 



