This biggest colony is found in the middle of the sample. Countless bacteria gather here.

Many bacteria are also found at the edge of the sample. I suspect that this "concentration" of bacteria at the edge of the smear is an "artifact" of the physical nature of the drop of water/smear that was used to form the sample rather than any action on the part of the bacteria.

Here, the cocci bacteria form in long chains of streptococci. These appear small even at 1000x.

Here are cocci bacteria from the mixed bacteria sample. These cocci bacteria are spherical, but they are too small to be seen clearly 

Bacilli appear in this picture. However, they are not clearly visible, because they are too small. Bacilli look like a hot-dog, and those bacilli are linked together forming a chain.