DIVISION II 



THE NATURAL HISTORY OF THE 

 GROUPS OF PLANTS 



THIS second part of our course is a study of the 

 Natural History of Plants. It investigates the habits 

 and structure of these organisms, and the relations of 

 their shape, size, color, positions, and cellular texture to 

 their modes of nutrition, growth, reproduction, loco- 

 motion, and protection. Whenever possible the plants 

 are to be observed as they grow naturally and undis- 

 turbed in their native homes. 



I. The Algae 



70. What is the structure and ecology of the Pleu- 



rococcus ? 

 Your record should bring out clearly : 



a. The exact appearance to the naked eye of 

 the organism as it grows under natural 

 conditions, and a description of those con- 

 ditions. Whatever annotated drawings will 

 not bring out is to be added in notes. 

 The exact structure of the organism, not only 

 in two dimensions, but in all three, with ex- 

 pression of the true size. 

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