It was noted by G. Legman [The Limerick, 1969] that...

"I do not insist that 'Sumer is i-cumen in' (about 1300), the oldest popular song in the English language, is in the limerick form, but a rather good case can be made for its stanzaic portion at least, and the possibility ought not to be overlooked. In modernized spelling:

Ewe bleateth after lamb, Low'th after calve coo; Bullock starteth, Bucke farteth- Merry sing cuckoo!

With all that has been written about 'Sumer is i-cumen in' - and it has taken almost a library of learned annotation to vindicate even the simple barnyard humor of the buck's crepitation at the highest note and melodic climax of the song - no suggestion has ever yet been made as to just what its prosodic form may be; and where, and when, and whether any verses similar to it may be found, in any language."