The Microscope. 359 



time, the protoplasm still refuses to flow, wliile other newer 

 mounts respond to the same treatment. lu all these experi- 

 ments great carefulness is needed ; slides and covers cleaned 

 with alcohol or other chemicals should not be used. I, there- 

 fore, have concluded to clean them as well as I can with pure 

 water, mount the specimens in clear or filtered rain water and 

 examine at once ; if the protoplasm is healthy and attached to 

 the cell walls, place it in a damp box, hoping in a little time, 

 from one to ten hours, to see the flow, but if the protoplasm is 

 separated from the cell wall, or is too j^ellow and coarsely gran- 

 ular or bubbly, it is dead or dying and worthless ; we, therefore, 

 throw it away without further coaxing. I have not yet entirely 

 decided whether the above described phenomena of shock to 

 the protoplasm was entirely caused by cutting and wounding its 

 continuity, or <vhether in part it might be due to the mounting, 

 but I am strongl}^ inclined to the former view. 



Apparently living onions with living shoots, from an out- 

 house loft without fire, where the temperature must often fall to 

 25° or 20°, and occasionally to 15° or 10° during the winter, 

 present various themes for study. A mount from one at 35°, 

 worked in a temperature of 50°, a very few cells exhibited the 

 protoplasmic flow at once ; in an hour the temperature had 

 risen to 65°, when I hoped to see a general flow, but the cells 

 were quiet and I saw no living bacteria of germination. The 

 cells were about dying and were full of little circles, evidently 

 gas bubbles pushing the protoplasmic granules into moraine 

 like masses on their circumference. Here and there a cell in 

 good condition was streaming beautifull}-. In this case the 

 cells were nearly all dead. There was not that evidence of 

 shock that we saw where the continuity of the protoplasm was 

 complete ; some others of these sprouting onions are further on 

 in the decline and show the elements of decay more positively. 

 The bacterium refringente and the micrococcus giganteus de- 

 scribed further on, are beginning to appear on the outside of 

 the cells ; they are often carried along by the water currents, 

 formed by drying out at the edges of the cover. These coarse 

 granules are very easil}' seen, and when thus floated along in 

 the water current are very likely to be mistaken by the inex- 

 perienced for the flow of the protoplasm, and very surely so if 

 he has not learned to know where he is focusing, whether on 



