FUCUS VESICULOSUS. 79 



ing the inner surface of the conceptacle ; they are long, nearly 

 transparent bodies containing small quantities of protoplasm ; 

 c is the nearly ripe oogonium. Two distinct membranes or 

 sacks appear at e and f. The central mass of protoplasm, as 

 soon as it has attained a definite size, divides itself into eight 

 distinct masses. About the same time that the protoplasm be- 

 gins to divide, the membrane e is ruptured at the top, and the 

 whole mass, with the second membrane, /, floats out. The eight 



Fig. 6. Antheridia, F. Vesiculosus. a. The Anther idia, b. Some 

 More Highly Magnified, c. Autherozoids. (400 diameters.) 



divisions contract upon themselves, forming round bodies until 

 they break through the two remaining membranes, and float out 

 in the water as eight uniform, nucleated, perfect spheres, called 

 oospheres, fig. 5. These are carried out of the conceptacle 

 by means of these hairs, whose only object is to throw the 

 oospheres from the conceptacle. 



In the olive brown fronds of the Fucus Vcsiculosus which 

 resemble the one pictured in every respect, excepting in the 



