Alicia Watkins’ embroidered microbes.
But streptococcus is a chain of circles. ):
Thanks for the note! I’m not a microbiologist (just a cross stitcher, with a M.A. in watching TV), so here’s the photo I based the strep pattern on: http://en.wikipedia.org/wiki/File:Streptococcus_pyogenes.jpg
As a stitcher, I could have patterned/stitched French knots rather than full cross stitches, which would have made it clearer that they’re chains of circles rather than little X’s, which is obviously what a full cross stitch looks like. (Anyone who gets the patterns from my shop is welcome to make that change when they’re stitching for themselves. Another change that might make it look a little more accurate is outlining each cross stitch (which would make them look like squares, but that’s probably better than X’s). I tried the outlining route but decided it looked worse, at least to me.)
In my case, I went for the regular cross stitches in part so that it would be easier to see the stitching, and in part to create a pattern that would be easier for a beginning stitcher to cope with (because French knots are a pain in the butt, and most of the other microbe patterns are already inaccessibly difficult for a beginning stitcher).
Those aren’t scientific reasons, so I get how the decision could be annoying, especially in light of how I try to use real images for patterning microbes and tiny things. There are better, more scientifically accurate stitch types that could have been used there, and I encourage everybody to try them out!