Yes. And if you want to see something really cool, take a look at a clear blue sky. You’ll notice tiny dots of lighter color moving quickly following constant short trajectories. These are your own leucocytes moving through the capilars right in front of your retina. The brain compensates the darker color of the predominant red blood cells, so you can’t see the capilars, but the white blood cells are translucent, so they appear as lighter dots!