Hi, I worked for a professor as a visiting student at XYZ university this spring on a research project. He delegated the supervision to one of his assistants who didn't really seem to care about the project. I should have worked with more focus instead of simply doing what he wanted me to. Regardless of whose fault it was, it went pretty poorly and although I managed to get a few results before the end, it wasn't very impressive at all. This professor is a pretty big shot and to be honest, I did learn quite a few things from it and this is my only foray into experimental work. The professor and I didn't interact much so his opinion of me is based entirely on his assistant's appraisal and that isn't great news for me. It was for credit and I ended up with a B+ and I left it at that. Now, I want to apply to grad schools next year so what should I do about this? I am applying to a bunch of a schools including XYZ university. Should I mention what happened or just not say anything about it? And should I even bother with an LOR from him or will it hurt more than help? I have two other undergrad research experiences and those went well. I blew a good opportunity, I know that. But it's too late to change it so what can I do now? Thank you, and Merry Christams!