The music stopped at points and the qs would have been audible to him...
Note the tails of the qs are turned to the left to clear the writing.
"He says there are not any fleas on qs," said Mollie with a reproving glance at Whistlebinkie.
If the qs or the Xs were gone, it wouldn't so much matter; but there's hardly a word that hasn't at least one E in it.
Latin quantum satis (as much as is enough)
quantum sufficiat (as much as shall suffice)