239- Paramecium is a good form for a study of ciliary action. 

 Study carefully if you have not already done so. Can the effective 

 stroke of the cilium he reversed? 



240. l:ffcct of NH 4 OH. Cvtolvsis Place Paraniecia in n/iooo 

 XH 4 ()H. Xote immediately the changes undergone hy cilia and 

 vacuoles. Dees swelling occur? Note especially if the surface of 

 the animal is lifted oft' while the cilia still remain beating on the 

 surface. Describe the changes during cytolysis. 



y. PROTOPLASMIC ROTATION 



A type of movement closely allied to amoeboid movement (see 

 p. 39). The leaves of Vallisneria, Chara, Nitella, Elodea, and the 

 stamen hairs of Tradescantia are well adapted for study of proto- 

 plasmic rotation. Use Elodea leaves in the following experiments. 



241. Study under the high power. Note time for a complete 

 revolution and the direction of rotation in adjacent cells. Draw a 

 diagram indicating the direction by arrows. Try warming slightly 

 the slide. Effect on rate? 



242. Place a leaf in isotonic sugar solution. Does the movement 

 cease? Cut leaf in half with sharp scissors and note if the cells near 

 the cut edge are affected in; any way. Can you observe any proto- 

 plasmic fragments moving in the fluid? 



243. Place a leaf in isotonic sugar solution and add a few crys- 

 tals of sugar. What is the effect of the resulting plasmolysis on 

 rotation? Does it finally cease? 



244. a. Place leaves in water one sixth saturated with chloro- 

 form. Effect on rotation? Remove to pure water again. Result? 



b. Try also ether water. Note that practically all vital processes 

 are slowed or abolished by these anaesthetics and that the effect is 

 reversible. 



245. Mount a leaf on a slide in physiological salt solution. Ef- 

 fect? Place non-polarizable electrodes at the ends of the leaf and 

 determine any effects of stimulating by galvanic and faradic shocks. 

 Result ? 



