RHODOPHYCE^, OR FLORIDE^E 



223 



Sphcerococcece. 



Nearly all the members of this family have much 

 branched fronds without foliar expansions, the 

 branches being frequently robust and of dense 

 texture. The gonimoblast is formed within the 



FIG. 70. a, Phacelocarpns Labillardierii natural size ; 6, cystocarp of 

 Gracilaria confervoides highly magnified. (After Thuret and Bornet.) 



thallus, and produces its cystocarp within a wall 

 formed of the peripheral thallus tissue which arches 

 outwards and has an opening at the apex for the 

 escape of the carpospores. The fruits consequently 

 look like semiglobular swellings on the branches. 

 Within this fruit-cavity and at its base there is 

 formed a placenta frOm which the spores are pro- 

 duced, and its surface is free from the over-arching 



