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USES OF THE CELL. 



This cell will be found useful not only for minute insects and parts 

 of insects, but it can also be employed to great advantage in the study of 

 Crustacea, Arachnida, Infusoria, Bhizopoda, Vermes, etc. In reality, 

 there is no minimum limit to the size of the cell provided one can obtain 

 glass tubes of small bore. I have cells which have a caliber of less than 

 0.45 millimeter, and an outside diameter of less than 1 millimeter, thus 

 obtaining a distance of less than 0.625 millimeter between the lower 

 surface of the "Zeiss DD" lens and the floor of the ceU tube. The 

 distance between the upper surface of an object lying in a cell of this 

 size and the lens would be small enough to make it possible to examine 

 the object with ease, using a high-power lens. 



However, it must be borne in mind that the greater utility of this cell 

 \n\l be in connection with lower power lenses and the camera lucida or 

 the photomicrographic apparatus, and that it serves primarily as a means 

 of preserving parts undistorted by pressure, such as is inevitable in the 

 ordinary technique of flat slide and cover glass, and enables the worker to 

 see successively four sides of the specimen. 



