Re: How do i delete picasa marked photos
Welcome to Android Central! Which device do you have? In the stock Gallery app, the Picasa icon means that the photo is stored in the cloud (specifically, your Google+ Photos albums, which is what Picasa became). The Gallery app usually doesn't let you delete cloud photos, but the Photos app does (the one with the pinwheel icon).
The other thing you can do is go to your Google+ Photos webpage, click More, then Albums, and delete the photos there. You might then have to go to Settings>Apps>All, select Gallery, and Clear Cache/Clear Data, then Force Stop. When you restart Gallery, the photos should be gone.