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L. HILLIS-COLINVAUX 





Fig. 66. if. incrassata. Section through very dark green gametangium fixed about 

 12-16 hours before the estimated release time of gametes. Gametes have been 

 differentiated, but separation is not entirely complete (Fig. 67). Gametes containing 

 chloroplast with starch, nucleus and mitochondria are separated from the game- 

 tangial wall shown in the upper right-hand corner by a thick layer of unidentified 

 material, electron-dense bodies and spherical bodies. Several oblique sections of 

 fiagella are included. The wall has an outer coating of fine fibrils. Stained with 

 lead tartrate. Scale bar is 1 [xm. 



present in the gametes as well. Between the gametes and the wall there 

 is commonly a layer of the electron-dense bodies, often two, three or 

 more thick, and a layer as thick or thicker than the wall of an unknown 

 material (Fig. 66). Some of these substances may provide the mucilage 

 that is released with the gametes as described later. Spherical bodies 

 and electron-dense granules also occur in the region between wall and 

 developing gametes. The wall has the fine fibrillar coating found in the 



