Vaucheria sessilis (GREEN FELT) 



A. Classification: 



Division I. Thallophyta. 

 Subdivision I. Algae. 

 Class II. Chlorophyceae. 

 Order. Siphonales (Siphon-algae). 

 Family. Vaucheriaceae. 



Genus. Vaucheria. (The only genus in 



the family.) 

 Species, sessilis (Vauch.) DC. 



B. Habitat: 



From your reading, class work, and material at hand, 

 ascertain and record at this point in your notes the 

 kind of localities where this plant occurs. 



C. Naked-eye Characters: 



Describe the color and "feel" of this plant, and the 

 general form of the plant-body. What is the signifi- 

 cance of the common name "green felt"? 



D. Microscopic Characters: 



1. Mount a portion of the material in water. 



2 . Is the plant branched ? If so, is the branching lateral 

 or dichotomous (i.e., forked)? 



3. Do you find cross- walls? Does the plant seem to 

 be composed of cells? What is the outline of its 

 cross-section? 



4. Can you detect any signs of division into root and 

 shoot? Do all portions of the filaments appear 

 equally fresh and vigorous? Describe. 



5. Do you find, on the end of any of the filaments, 



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