This is Narcissus Telamonius Plenus. I bought some from the specialist grower Shipton Bulbs who reckon that it is the double flowered form of the wild N. pseudonarcissus; as such it may be a cultivar but perhaps it is a naturally occurring mutation.
 They note it is similar to N. Van Sion which was introduced from Holland in the 17th. century; its actual origin may well be lost in the mists of time.