Is There a Limit to Number of Page Templates?

… Basically the question is in the title. I’m dealing with a large score, and finding it necessary to have several different page templates, all based on the “Default” page template… But when I created my eighth page template, one of the others seems to have disappeared from my list…
So really, I have two questions:

  1. Is there a limit to the number of page templates I can create overall?
  2. Is there a limit to the number of templates I can create based on another page template?

None that I know of, I’ve used as many as 11.