Possibly Tragopopagon pratensis, Jack go to bed at noon.

I think they are Coltsfoot , Tussilago farfara. They flower very early in the year before any leaves appear. They used to be quite common but I haven't seen any for years now.

my thought is coltsfoot too. what height is it? if its less that 9" tall then that's what I'd go for.

if taller 1ft it could be one of the hawkbeards Crepis
or taller still 2ft then sowthistles

we need to see some of the foliage, are there any on the stem or behind the seed head?

Thanks all. I am thinking it IS Coltsfoot and went down to riverside again today but they are more or less over leaving just some stalks. We couldn't find any leaves but the stalks do have little bumps all along the stem as if there had been leaves. Quite excited as I had forgotton all about Coltsfoot as I hadn't heard the name since I was a young girl (and that is a long, long, long time ago!!), so it brought back memories of nature walks with my Mum and Dad most weekends. Maybe the last flood brought the seeds earlier this year as the water certainly brought an abundance of Greater Celandine...have never seen so many. Anybody else notice this?