They are now considered to be both Scilla. Leastways as long as you take out the Scilla which have now been re-assigned to other genera.
Which Scilla and soi dit Chionodoxa do you mean?

Thanks owdboggy. I have some in my garden which I've inherited. I saw them and 'knew ' they were Scilla, but then I was looking at another members pics of Chionodoxa and realised I didn't have a clue which mine are. If you go to my photos...7th and 9th pics...you will see them. Thanks! :)

A real good reference for bulbs can be found at pacificbulbsociety.org in the photograph section. They mention how some of the Scilla were moved to Chionodoxa. It's also helpful if you are thinking of getting something unusual. Just click on a photo to enlarge.

Thanks Wylie! That's helpful!