2 5 



ALGJE 



organ, antherids and ' sexual 

 spores' (oospheres), formed 

 within the sphaceles ; but 

 Janczewski believes that the 

 supposed antherozoids are in 

 reality the zoospores of para- 

 sitic Fungi (Chytridiaceae), 

 to whose attacks these sea- 

 weeds are especially liable. 

 Pringsheim describes two 

 kinds of fructification pro- 

 duced by Cladostephus, one 

 in the autumn, the other in 

 the winter ; but Wollny sug- 

 gests that both the autumnal 

 fructification and the so- 

 called unilocular sporanges 

 may be due to the attacks 

 of parasitic Chytridiaceae. 

 The Sphacelariaceae have a 

 strong tendency to multiply 

 by means of buds, gemmae, 

 or propagules. Janczewski 

 describes the mature gemmae 

 as consisting of a pedicel and 



FIG. 223. Sphacelaria cirrhosa Ag. a, natural size ; 

 b, branch with propagules, a (x 100) ; c, filament with 

 unilocular zoosporange ( x 100). (After Hauck.) 



FIG. 224. S. cirrhosa. , filament 

 with propagule, b ( x 140). (After 

 Reinke.) 



