Insect and Spider Identification: CLOSED: CLOSED: CLOSED: Is this some kind of Cocoon?, 1 by bluemerle

bluemerle wrote:
Before I got my Digital Microscope I sent pics of these things using just my phone camera. FlapDoodle couldn't identify the out of focus pics, thought it might be a disease.

Could we try again, please? Also, I put some of the 'infected' leaves in a container, closed the lid and forgot about them. When I opened the container a day or two later, I found they HATCHED!! Pic was with phone camera, but it proves that they're insects, not a disease. Yes, the Bell Pepper leaves with these on them were the ONLY thing in the container.

I've controlled the mass infestation, but I still see them in smaller numbers.
Could you ID and tell me if they are harmful, please?
Thanks, Diane