Nikon Coolpix 950 camera, Olympus inverted microscope with Microscope Plus eyepiece adapter.

These peritrichs are colonial  and share a common stalk. This image shows  both animals feeding with their oral cilia moving. This specimen was taken from the Union Canal, Edinburgh in June 2002. They were attached to a strand of filamentous algae. 

In this second image the right hand animal has stopped feeding. Note that only one animal contracted rather than both at the same time. This fact , together with the arrangement of the feeding cilia, suggests that they probably belong to the genus Opercularia. 

This peritrich was was found in the same water sample as the previous specimen but was solitary and possessed a lorica. Periodically it contracted within its lorica.