AMCEBA. 



Dr. H. S. Jennings has described a method of cultivating 

 Amoebce and other Protozoa for class work. Glass dishes about 

 3 inches deep and 8 or 9 inches in diameter are crowded full 

 of various water plants, especially Ceratophyllum, Elodea, etc., 

 and are then filled with water and allowed to decay. Several 

 such dishes should be prepared so that a supply will be certain. 

 After a certain time (say about two weeks) the layers of plants 

 at the surface of the water will be covered with a brown slime. 

 Some of this should be scraped from the plant, placed on a 

 slide and examined under the microscope. As frequently the 

 Amoebce in a culture last but two or three days, several cultures 

 made at different dates should be on hand. These cultures 

 will also afford other Protozoa such as Arcella, Difflugia, Stentor, 

 Paramcecium, etc. 



The slide with the slime known to contain A.mcebce is 

 covered with a thin cover-glass and examined under a 

 rather high objective (|- inch: Leitz No. 5, Zeiss C). When 

 Amoeba is found note the following points: A central 

 body from which radiate slender prolongations (pseudo- 

 podia). Are the pseudopodia regularly arranged around 

 the body or are they more numerous on one side? Are 

 they simple or branched? 



In the body make out a granular internal portion, the 

 endosarc, covered by a clearer external layer, the ectosarc. 



Do both layers enter into the pseudopodia? Watch 



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