Are these Stentors?

[Jbailey]

These two well-stuffed critters were photographed in a water sample from a local pond. I think they are some kind of Stentor but there was no visible cilia or mouths. They moved fairly slowly.
Help with ID, please.

The magnification was 100X with achromatic optics and a Lifecam webcam. Lighting was via a home-made LED system.