12. Livingston : Chemical stimulation of a green alga 



few palmella cells remain. Filaments are inhibited, thus giving the 

 palmella form, in strengths from 5/// 1, 000,000 to 5///1 0,000,000. 

 The palmella form in solutions of this salt is usually somewhat 

 bluish green in color. There is an acceleration of zoospore pro- 

 duction at nl 1, 000,000. At /// 10,000,000 the culture is normal. 



Figure 8. Palmella from k/io,ooo Co( NO.,).,. 



Figure 9. Palmella and zoospores from 5»/l, 000,000 CoS0 4 . 



Figure 10. Filaments from w/i, 000,000 CoSO,. 



Figure ii. Palmella from «/i ,000,000 Cu(NO s ) 2 . 



{Fig. 11 illustrates typical palmella from ;// 1,000,000 concentra- 

 tion.) 



//. Copper sulfate (CuS0 4 ). —The sulfate again agrees with 

 the nitrate. {Fig. 12 shows the appearance of palmella in 0/1,- 

 000,000, concentration.) 



