What's Smaller Than A Pygmy Shrew?

A pygmy shrew is small, it's among the smallest of mammals. What could be smaller? Yes, protozoa are very small. Indeed. And there are many things even smaller than that- things so small that we can't see them with our own eyes. We need the help of a microscope. But there are some particles so small we can't see them even with a microscope, and we can't measure their exact size! Explore the large world of the very small. 32 pages.