The leaf pictured was just one of many that had fallen below the Victorian Blue Gum, Eucalyptus globulus ssp bicostata  .  But it was probably the biggest, and had the best patterns on it. I’m guessing that the patterns are made by a fungus, but would like to have some real information on these markings. What causes them? Why are they circular? Is there a function to this shape? Is it just a fungus spreading out in a big raindrop? Regardless, I think it has an intrinsic beauty. [Submitted by Pete Kelly, Creek Junction.]