THE ALG.E 25 I 



c. Both the vegetative and the reproductive 



parts. 



d. Ecological connection between structure and 



habits. 



71. What is the structure and ecology of Spirogyra ? 

 Answer as for Exercise 70. 



72. What is the structure and ecology of Fucus ? 

 Answer as before. 



73. What is the structure and ecology of a typical 



Red Seaweed ? 



74. From your own studies, from the specimens and 



pictures examined, reading, and other sources 

 of information, concisely describe : 



(1) the range of habitat in Algae ; 



(2) of color; 



(3) of size ; 



(4) of shape ; 



(5) of texture. 



75. Prepare a concise essay, not over two hundred 



and fifty words, on the Natural History of the 

 Algae, emphasizing their ecology. 



Materials. The aim is to give first a typical unicellular 

 form, reproducing by fission, and a filamentous conjugating 

 form next. Zoosporic forms can hardly be used for study of 

 processes of reproduction, because of practical difficulties. As 

 this study is more ecological than systematic, it matters little 

 just what forms are taken as long as they are typical. In 

 summer many Algae are available, but in winter I have found 



