I PRACTICAL DIRECTIONS 239 



not extending to the periphery, so that a clear ectoplasm can be dis- 

 tinguished from a granular ettdoplasm. The granules render the flowing 

 movements of the protoplasm visible. 



3. The food-vacuoles in the protoplasm, containing fluid, and often 

 also food particles. 



4. The contractile vacuole, containing' fluid, and its rhythmical con- 

 tractions. ' 



S- The protrusion and retraction of the pseudopqds. Sketch a 

 specimen several times at short intervals, noting the direction in which 

 the granules flow. 



6. Look out for specimens undergoing multiplication by binary 

 fission, and also for encysted individuals. 



7. Run a little dry carmine or indigo under the cover-glass, and 

 note that the particles can be taken in at all parts of the surface. 



8. Stain with methyl-green (see p. I2i), This will kill the animal, 

 and render the micleus distinct. 



9. Permanent preparations, showing the nucleus, may be made on 

 the slide as follows : — 



Place a drop of water containing Amoebae on a slide, and soak up 

 with blotting-paper as much of the water as is possible without carry- 

 ing the Amoebae along with it. Fix (see p. 136) with a drop of 

 absolute alcohol, stain (a staining-fluid called picrocarmine is better 

 than borax-carmine for this purpose), wasfi carefully with weak and 

 then with absolute alcohol, and add a drop of turpentine — or better, 

 oil of cloves. Soak off the excess of oil of cloves with blotting-paper, 

 and mount in Canada balsam. 



