The image above shows three small-flowered clematis: left to right Clematis texensis, the hybrid 'Betty Corning' and then Clematis glaucophylla. These small-flowered sorts are in contrast to their large-flowered, voluptuous, and much better known relatives. What they lack in overweening splendor they more than make up with grace and charm.
At first glance the flowers of Clematis texensis and C. glaucophylla suggest small strawberries on a vine. Garden visitors unfamiliar with these plants and trying to figure out what they are will get no help from the foliage: there is something vaguely pea-like about it.
I've included 'Betty Corning' here because, according to tradition, it is a hybrid of Clematis crispa, another member of the Viorna group of clematises which includes C. texensis and C. glaucophylla. I just read the Missouri Botanical Garden account of this cultivar and it includes this information: " ‘Betty Corning’ (C. crispa x C. viticella) is a late, small-flowered, semi-woody, climbing vine that was first discovered growing in Albany, New York in 1932. " Although that account does not say so in so many words, that suggests to me that the parentage is a guess. It does look a bit like Clematis crispa, and the flower size is a good match for the other purported parent, Clematis viticella. In spite of the reported parentage I've often wondered if it might be a hybrid of Clematis integrifolia.
Although I have not done this yet myself, I'll bet that if Clematis texensis and 'Betty Corning' were planted together on the same support the result would be very nice.