THE RED ALG^ 



489 



of certain branches, 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 (/, 0- Fertilization is effected 



Fig. .319. — Bladder-wrack; a, vertical section through a conceptacle (»«) 

 showing the female gametangia; h, 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 (<7) shown 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. 6-/, ^\^, g, ^f^. (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 



