Later pages canonicalised to the first
IssueHigh priority
Pages after the first in a series that name the first page as their canonical.
Why it matters
That says every later page is a copy of page one, so search engines index none of them - nor, often, what is listed only on them.
How to fix it
Give each page of a series a canonical to itself.
Skitter runs this check on every crawl, and lists each page it finds with the evidence: the header, the tag or the link that gave it away.