Hmm! Maybe Ornithogalum sp. http://www.google.co.uk/search?q=Or...urce=og&sa=N&tab=wi&ei=8DZGT7erG4K-8AORz_2zDg A close up pic would really help.
I agree w/ SS. Common name Star of Bethlhem. Here is "Wiki" site to check out. http://en.wikipedia.org/wiki/Ornithogalum As usual there are several types. barb