Catalpa blossoms (actually catawba blossoms)

I pass this tree when I am out walking in the neighborhood.  I remember the two huge catalpa trees at my grandfathers farmhouse.  There was a 3 inch pipe between them supporting a porch swing.  The shade was deep (and cool!) enough that there was never any grass (or other plants) under the trees (or perhaps we just trampled everything down playing there)  The Catalpa tree is a member of the trumpet vine family (I didn't know that!).  What is really weird is that it's name really should be catawba (the name given by the native Americans),  but the botanist who first described it spelled it wrong when it was first described.  Botanical naming rules require that the spelling used in the formal scientific description has to be retained for the scientific name (I didn't know that either).