GROUP I. THALLOPHYTA: ALG^E : PH^KOPHYCl':^. 265 



V 



1m 



/ 



11 



FIG. 191. A Eight oospheres extruded from the oogonium, surrounded by t..e i.iiior iyer 

 of the cell-wall: B contents of an antheridium set free, surrounded by a layer of the cell- 

 wall : C antheridium : D section of contents of an oogoiiium showing the divisions accom- 

 panying the development of the oospheres : E oospherps set free in consequence of the 

 rupture of the layer of cell-wall by which they were surrounded when first extruded : F 

 and H oospheres, with spermatozoids : Gf spermatozoids. A-F Fucus platy carpus; GH, 

 F.vesiculosus. (C and G x 540; other figs, x 240: after Strasbnrger.) 



