The following photos are of C. cordatum BSWJ2812 and BSWJ4841, flowering in late August, 2011. Both forms are from seed collected in Japan.
The slight hump on the upper surface of the flower, which can be seen on the main sequence photos, is far more pronounced in these examples.
The edges of the upper three tepals are bent upwards whereas there is no such curvature on the lower three, but I'm not sure if this curvature accounts for all of the hump.
(Photos: Moira Bolt)
