SECTION VI. THALLOPHYTES (ALG^ AND 

 FUNGI) 



A. THE ALGJE 

 PROTOCOCCUS (PLEUROCOCCUS) 



1. Habit and Habitat. Note the appearance of Protococcus 



on bark, boards, or stones. Has the green incrustation 

 any definite form or structure comparable to that of 

 the higher green plants ? Do you see any evidence of 

 roots, stem, or leaves ? Do you know whether Proto- 

 coccus ever lives in water, like the other fresh-water 

 algse ? Is Protococcus on bark or stones xerophytic or 

 mesophytic in habit and habitat ? 



2. Structure. Scrape off a little of the green incrustation 



formed by Protococcus in a drop of water on the 

 center of a glass slide. Be careful not to remove 

 pieces of bark or dirt with the plants. Cover and 

 press out gently under the cover glass with a dissect- 

 ing needle. Examine with the low power of a com- 

 pound microscope. 



a. What is the nature of the green masses observed under 



a low power ? Are they composed of cells ? Do you 

 find any single green cells ? What constitutes a 

 Protococcus plant ? Is it unicellular or multicellular ? 

 Do you find chloroplasts, cell wall, etc. ? 



b. Sketch two or three green masses to show their struc- 



ture as you observe them. Label the parts in terms 

 of cells and cell structures. 



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