These are called posy bowls, as much as I can find a technical name for them. I have five now I think. An Aunt gave me my first one. Then I found one in an abandoned house, sort of abandoned anyway. Then I bought one at a garage sale. Then I found/ bought a couple which were at GoodWill last year. They had a few but only a couple were in good shape. I didn’t want to pay $5 for one that was chipped. 
They are bone china and made by different companies, like Royal Doulton. Most of mine are not Royal Doulton though, I can’t think of the company name right at the moment. If I saw it I would have a flash of brilliance and know it right away. 🙂
These trilliums were on Ebay but I couldn’t bid on them at the time. I still think about them. Trilliums are the flower of Ontario and one of my favourite wildflowers too. Someday my trilliums will come. 🙂