How exactly is the output of the XOR step in PBKDF2 used?

I'm attempting to diagram PBKDF2 for a school project and I'm not 100% sure how to represent the XOR step. Specifically, I'm confused as to whether the output of the XOR step is used in subsequent rounds or if it is calculated each round in order to make all rounds identical. Here's a diagram showing what it might look like if the answer is that the output of the XOR step is not used as an input to later rounds. Is this correct?

This diagram is based on the one on the very excellent blog post here: http://ift.tt/1ygSC4W