Cuckoo Flower or Lady's Smock

Another spring classic, this is found in damp grassy ditches and field margins. Cardamine pratensis has one of the longest lists of local vernacular names in Mr Grigson's master work. It appears to be widely associated with bad luck if picked so is not really used medicinally. In the old days smock was use as innuendo for a female desired sexually, as in 'a bit of skirt'. 
It's part of the Brassicaceae or cabbage family, formerly known as the Cruciferae or crucifers on account of their having four petals arranged in a cross. I found this today walking along the bank of the Ouse.
The more I reflect, the more it's as if some massive switch was thrown whilst we were away in Morocco, signalling the start of Spring proper. This has been especially noticeable with the garden bird-feeders. Before we went I was re-filling the big seed feeder every two to three days. I filled it when we got back and

more than a week later it's still not empty, with the ones nearest the house virtually untouched. The peanuts have been shunned completely. 
I'm sure the reason for this is the dispersal of wintering flocks now that the breeding hormones have kicked in. The birds have all become territorial and consequently anti-social (barring the house sparrows, wherever they are). 
On my walk today I saw two crows' nests with sitting birds, along with magpies and blackbirds gathering nesting material. I also heard the first willow warbler of the year, saw three peregrines at the same time (a male and female with another male somewhat apart) and a buzzard. Yesterday I saw that the ravens have two fledglings only days away from leaving the nest.
Nice.