SPIROGYRA QUININA. 35 



2. The slippery feel, when the plant is taken between the 

 fingers. 



Float a small amount of material in water over a white 

 surface, and observe 



3. The fine unbranched filaments of which it is com- 

 posed. 



4. Their uniform diameter. 



5. Their length. 



Place some in alcohol, and after some time notice 



6. The color imparted to the alcohol by the chlorophyll. 



B. Mount a few filaments, and notice the single row of 

 alternating light and dark dots, indicating the single row 

 of cells. This can not be seen in all specimens. 



C. THE FRUITING PLANT. Mount a few filaments 

 from a fruiting mass, having them well separated on the 

 slide, and search for 



i. Paired conjugating filaments, some cells of which are 

 empty, some with dark colored dots, the zygospores, 

 and a few often remaining unchanged from the vege- 

 tative condition. a 



MINUTE ANATOMY. 



A. GENERAL CHARACTERS. Under low power, 

 notice 



i. The indefinite length ; if traced to the end, the fila- 

 ment will probably be found broken. 



5 The presence of small particles of dirt and other debris makes it diffi- 

 cult to distinguish the zygospores and conjugating filaments with cer- 

 tainty, and it is always best to verify the observation with the compound 

 microscope, if possible. 



