Monsters of the Shallows

We found these monsters (320 um long, or about a third of a millimeter, or 1/64th of an inch) in some scum from Lake Hodges.

They are paramecia, a type of protozoa. Here they are at various levels of magnification with some body parts identified.



Here are a bunch of them swimming around at 40x. You can also see some smaller creatures swimming around, but they are just tiny dots. Watch for one at the top by the pointer get stuck trying to squeeze through an opening that's too small.



Here they are at 100x. Here you can see the regular-size critters swimming around and you can see how big these monsters really are. This is also a good magnification to see the two contractile vacuoles which expel water. If it didn't have a way to pump out water, the little guys would explode!



Here's a movie at 400x. The monster is so big, we can't even see the whole thing at once at this level. We can also start to see the cilia moving and we get a pretty good view of its mouth.



This last one is at 1000x. This is actually the first movie I took, and at first I thought it was just an air bubble. And then I realized it was moving! You get a very close-up view of the water pumps and the mouth, plus little creatures get swept away from the monster's cilia. I also thought it was interesting to see how much stuff is going on inside the paramecium--it not just a bag of molecules.