Silene latifolia ssp. alba ..
Flowers erect on short stalks or sessile, open in afternoon.
Male flowers with 10 stamens and female flowers with 5 styles are on separate plants
Silene noctiflora ..
three styles in flowers; plant is sticky all over.
(Silene latifolia) - Very similar. Flowers have five styles; plant not sticky.
How many styles does it have, but if you only have the one plant then you have a problem if it is a male flower which are on separate plants but one of your photos is showing something in the middle.
I assume they mean Silene latifolia is the same as ssp alba, but if not both are probably similar. The test now is, is the plant sticky? The ballon behind the flower often varies in colour.
There is a description of Silene noctiflora on a wild seed site here which I trust, the flowers on noctiflora are much more deeply cut and flowers white or pink.
http://wildseed.co.uk/species/...
