The hot weather has brought out the jellyfish in the Marina. I didn't recognise this one but thanks to my book and the power of the internet, it appears to be a 'Rhizostoma pulmo' commonly known as the 'barrel' or 'dustbin-lid' jellyfish. This one was approx 30cm in diameter but they can reach 90cm.

Thankfully swimming is not allowed in the Marina. Mind you, there's no way you would have got me in unless of course I fell in! Far too many lurking around for my liking.