THE RED ALGyE 



489 



of certain l^ranches, and these emit minute, spherical gametes 

 having no flagella or other means of locomotion. At the tips of 

 other branches female gametes appear, each in the form of a flask- 

 shaped cell with long, slender neck (/, /). Fertilization is effected 



Fig. 319. — Bladder-wrack; a, vertical section through a couceptacle {^^) 

 .showing the female gametangia; 5, female gametangium beginning to 

 form its eight gametes; c, the same, beginning to set free its gametes: 

 d, male gametangia (shaded) from which come ciliate gametes like the 

 one {g) show-n near by; e, female gamete surrounded by numerous male 

 gametes which cause it to revolve in the water: /, young plant produced 

 directly from the fertilized female gamete. /)-/, ^1", g, ^Ji. (Thuret.) 



by fusion of male gametes with the projecting end of a female gamete 

 to which the little spheres have been brought by currents in the 

 water. After fertilization the basal part {I-V, c) gives rise to several 

 branches, each of which finally produces at its tip a spheroidal spore 

 that soon separates, and attaching itself to some support, developes 



