Isoetes (QUILLWORT) 



A. Classification: 



Division III. Pteridophyta. 

 Class I. Eusporangiatae. 

 Order. Isoetales. 

 Family. Isoetaceae. 

 Genus. Isoetes. 

 Species, (e.g., lacustris.) 



B. Habitat: 



Some forms grow on the bottom of ponds, others in 

 moist meadows, or on the margins of bodies of water. 



THE SPOROPHYTE 



C. Naked-eye Characters: 



1. General Features. 



(a) Note the differentiation of the plant into root 

 and shoot, and of the shoot into stem and leaf. 



(&) Make a sketch, natural size, showing the 

 general appearance of the entire plant. 



2. The Stem: 



(a) Without removing any of the leaves or roots, 

 ascertain all you can about the shape, size, 

 branching, and other characters of the stem, 

 and describe. 



(b) With a sharp scalpel, make a cross-section of 

 the stem through the middle, being careful not 

 to remove any of the leaves or roots. 



(c) Describe the outline of the stem as seen in 

 cross-section. Note the longitudinal furrows 

 which give it a lobed appearance. 



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