THE MICROSCOPE. 



iVIARCH, 1896. 



Number 39. 



New Series. 



Objects Seen Under the Microscope. 



By CHRYSANTHE-MrM. 

 XXXT.— DIATOMS, DESMIDS AND FRESH-WATER ALG.^. 



Diatoms, desmids and fresh-water algae are among tlie 

 lowest forms of minute aquatic plants. The diatoms and 

 desmids closely resemble each other and are formed of a 

 single cell. These cells vary greatly in structure and 



lieauty, and t'uruisli some of the most interesting objects 



'.^^smm 



which the young observer meets in his study of pond life. 



Desmids are always found in the sweetest and clearest 

 water. They are usually green in color and move with 

 a slow stately movement in one direction. The sac which 

 holds the desmid may be torn or broken, and the jelly- 

 like coloring matter forced out, leaving the edges of the 

 sac ragged. 



The diatoms when alive are usually brown and move 



