More lettuce pictures

They are now too tall to be inside the jiffy greenhouse. And, I guess that I'm supposed to be thinning them, I am always afraid to do that. What if I pull out the wrong one? What if I pull one out and it's attached to the others, and pulls them all out? Or, should I leave them longer?

I don't know, but, I'm sure looking forward to little bibb lettuce heads!