Basic reporting

See below

Experimental design

See below

Validity of the findings

See below

Comments for the author

Note from staff: The original comments from this reviewer did not make it into the system correctly. Therefore Dr Weishampel supplied comments direct to staff as per the text below:

my review was very simple: The Farke et al. MS is spot- on, well written, and complete as far as the bony descriptions and the synthetic discussions go. The only thing I would ask them to spend some more time on is the issue of the S-Loop of the crest and its phylogenetic distribution - parasaurolophins don't have one (that is, they've highly modified the vestibule to make their entire crest) and corythosaurins have an S-Loop. That's about it. In lieu of an official review, I hope that this will suffice.