SEX UA L KEPK OD U CTIOxy. 



287 



Simple ovaries occur only in the algre and fungi, \\'here they 

 are known as oogonia or carpogonia. Thev are either pro- 

 duced by the modification of one of the cells of a filament 

 (fig. 325), or they are the terminal cell of a siiecial branch 

 (fig. 30S). Usually the ovary is decidedly larger than the or- 

 dinary \'egetati\-e cells. Tiie fertilized egg often becomes a 

 resting s|)ore (fig. 32c;). 



In the higher alga;, especially the marine algre, the ovaries 

 are often aggregated in special pits, the conceptacles, as in 



Fig. 326.— A section tlirou^ti a female conceptacle of \i\^Ad-^T wtaqV^Fiiciis vesica/ lo- 

 siis) \ sliowiug form of pit. tlie numerous tiairs witli wliicli it is lined, and o^'aries in 

 various stages of develo]iinent. In the tissue about the pit note the cortex of densely 

 placed celLs and the loose network of filaments in the interior. I\Iagnified 5odiam. — 

 After Thuret. 



Fucus (figs. 42, 326). Here the ovar)- is formed b)' the en- 

 largement of the terminal cell of a two-celled outgrowth from 

 the surlace (fig. 327). The eight eggs are set free and are 

 fertilized in the ^^"ater b^'the motile sperms (fig. 324). They 

 grow at once into new plants. 



The simple o^'ar"^' is surrounded in Cliara (fig. 313) by a 

 jacket of spirallv coiled cells, which grow up from beneath it 

 and make it look as though it were compound (* 390). 



