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Hi 

The large protozoan Stentor is common in my garden pond at the moment, so these images I've taken may be of interest. Stentor is a common large trumpet-shaped genus of protozoa (some species are up to ca. 2-3 mm long) when attached to a surface, but these images show the shape and detail of a green species when free swimming. It then adopts an oval shape, narrower at one end. 

regards 

Dave Walker


Lighting - bright-field 
The 'trumpet' end when free swimming. 9x objective.
[img]http://www.microscopy-uk.org.uk/dww/forum/stentor1.jpg[/img]


Lighting - bright-field. 9x objective. 
The posterior end when free swimming, note it narrows. Cilia can just be seen at the end.
[img]http://www.microscopy-uk.org.uk/dww/forum/stentor2.jpg[/img]


The green colour of this species isn't clearly shown in normal lighting. This is dark-field lighting which shows the green colour. Vacuoles can also be seen.
[img]http://www.microscopy-uk.org.uk/dww/forum/stentor3.jpg[/img]
Lighting - phase contrast, 20x objective 


This is a special type of lighting that shows the cilia more clearly. These cilia are at the narrow end when free swimming. 
[img]http://www.microscopy-uk.org.uk/dww/forum/stentor4.jpg[/img]

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