What do you call the tail of the email?

When I hit "reply" to an email message, unless I edit it out, the message I am replying to is contained in the new message. After some back and forth, a long "tail" accumulates. I am preparing an archive of email correspondence. I need to explain that I removed signatures and "tails." I don't know how to explain this thing I call a "tail." In my draft I am calling it "prior messages," which doesn't seem terribly clear. Is there a term for this? Or can you help me make one up that will be self-explanatory?

The enclosed archive of email correspondence includes all messages and headers but no prior messages or signatures.

Solution 1:

The enclosed archive of email correspondence includes all messages and headers, though quoted text from previous messages has been deleted for brevity.

This phrase, in bold font above, is copied from https://en.m.wikipedia.org/wiki/Posting_style

When a message is replied to in e-mail, Internet forums, or Usenet, the original can often be included, or "quoted", in a variety of different posting styles.

The main options are interleaved posting (also called inline replying, in which the different parts of the reply follow the relevant parts of the original post), bottom-posting (in which the reply follows the quote) or top-posting (in which the reply precedes the quoted original message). For each of those options, there is also the issue of whether trimming of the original text is allowed, required or preferred.
[...]
Quoted text from previous messages is usually distinguished in some way from the new (reply) text. [...]

On a side note, trimming such text seems very error prone, especially if there have been interleaved or bottom replies. It could also be misleading if emails are presented out of context and order.

Solution 2:

I use email exchange to describe the newest message plus the long tail that has accumulated. If you apply that to your example, you could say:

The enclosed archive of email correspondence includes only the newest messages and headers from each email exchange.

OR

The enclosed archive of email exchanges includes only the newest messages and headers from each email exchange.

Solution 3:

As Janus mentions in his comment, the tail you refer to is the result of the e-mail client automatically quoting what you're replying to. Therefore, I think the noun you're looking for quotations.

This is how I'd write your sentence:

The enclosed archive of email correspondence includes all messages and headers, with automatic quotations and overly long signatures removed for the sake of clarity and brevity.

The automatic bit I have added because I assume you haven't deleted any in-line quotations that some people use when addressing multiple points discussed in previous e-mails.