Violets May Be Yellow, or ....

I don't remember my botany professor's name, but I remember his saying, "Blackberries are red when they're green."  I can imagine him saying, "Violets are yellow," but that wouldn't have made sense when I explored forests with him in the Southeast where all the violets I remember seeing were violet.  Here in the northern Sierra, lots of violets are blooming now.  From the top:  The Wood Violet, Viola lobata, is blooming in the hills surrounding the FRC campus as well as along the paved path up to the college from the parking lot.  The Pine Violet, Viola pinetorum, was blooming yesterday on the hillside across the railroad tracks from Oakland Camp, as was the only violet one here (bottom two photos), the Western Dog Violet, Viola adunca.  The only white one I've seen in these parts was blooming in the Butterfly Valley Botanical Area.  That would be Macloskey's Violet, Villa macloskeyi.  And, of course, Pansies are violets.  Confused yet?  What if this genus had been first discovered in California, and the first ones seen were the yellow species?  They wouldn't have been named Viola.