This pattern dates to around 1957 - and is a fantastic piece of mid-century modernist British ceramics.
This is one of Midwinter's harder to find patterns - called Quite Contrary, and it was designed by Jessie Tait - as annotated on the base of each bowl.
They are each 7 ½ inches in diameter.
Three are in really good vintage condition with no nasty chips or cracks. Sadly the fourth in my little set seems to have a discoloured scratch of the base (as photographed) - it might bleach down - but I have not attempted that.
Each good plate is priced at a fair £10 each; and the one with the condition issue has a £5 price tag - so £35 for the set shown here.
I am also listing four matching plates on my site - would try and get some postal discounts on these it you want the two sets.