176 PHYLUM II. CHLOROPHYCEAE 



water, and watch the production of zoospores. Enteromorpha, 

 which is common in brackish waters in the interior, may be 

 substituted for Ulva. 



(/) Study Ulothrix in like manner. It may be grown in an 

 aquarium very easily, so as to be obtainable at any time, even 

 in the winter. Draparnaldia may be found in running fresh 

 water. 



{g) Specimens of Oedogonium may be obtained by examining 

 the small sticks and stems of aquatic plants from quiet waters. 

 They may be recognized by the enlarged oogones. 



{h) The Disk Algae occur in fresh-water pools as little green 

 masses adhering to leaves, sticks, the stems of living plants, 

 etc., where they should be sought. The sexual process and 

 the development of the sexual organs occur in May, June, and 

 July. 



LITERATURE OF CHLOROPHYCEAE 



Frank S. Collins, The Green Algae of North America, Tufts 

 College, 1909. 



G. S. West, A Treatise on the British Fresh-water Algae, Cam- 

 bridge, 1904. 



