"Duplicate title tags" and "Duplicate meta descriptions"
Rlilly, It occurs that there may be another issue entirely... As you've framed your question, I think you've gotten good answers on this thread, but you may not have described the problem fully.
What are the circumstances of the change? You need to find the origins of the problem.
Eg, if you've made any changes to the site recently, then these might be...
a) simply changes in url naming conventions...
, they might be be old versions and new versions of pages built on the same page framework, and also with slightly different naming rules.
If the latter, the content will be not be the same... ie, it's not safe to assume the only changes in these pages is a difference in title case. Because Google is case sensitive with regard to urls... it would report the different capitalization/lc combinations as entirely different pages, and just report top level duplications of titles and meta descriptions.
If these pages have different content, then the 301s might create even more confusion, as they could overwrite changes. Before doing anything, you should look at some of the content of these pages as well, and compare... and track back to the origination of the problem. If you had version control, and this is the issue, that would be immensely helpful.
Otherwise, to help track which pages overlap, use a spidering tool... or do site searches for unique phrases on the page (ie, search for them in quotes). There's a huge variety of possibilities, depending on what your work flow was.
I hope this makes sense. It's sometimes hard to deal with hypothetical situations which haven't been described in sufficient detail.