Database of Cultivar Names???

[psoque]

I am wondering if there is a good online database of named cultivars. I recently purchased a particular named cultivar of C. Memoria Robert Strait. The cultivar I used to have was named 'Lakeland," but the one I recently purchased was labeled 'Islander Delights' on the tag. When I go online at various growers, this particular cultivar is sold in various permutations, including 'Islander Delight,' 'Islander's Delights,' 'Islander's Delight,' etc. I would like to know which is the correct name.