[Pyro7480]

I think the most well-known melisma is "Angels We Have Heard on High," on the word "Gloria."

[AnAmericanMother]

Probably right. Eighteen on "Glo" (they really have to be on one syllable). That's good.

The O Sacrum Convivium is not in my short Liber . . . and my choir book is at church. I think it's as long or longer than the "Gloria" -- but it goes at a slower tempo, so that may be why I ALWAYS run out of air somewhere in the middle . . .