Heard at St Andrews University, 1959:

Little boy kneels by the sitting-room fire,
Little face flushed with abnormal desire.
Meow! Meow! Oh, what is that?
Christopher Robin is sodding the cat.

Chicken Charlie: The Confederate parody you mention must be the origin of a curious version of "Mary Had a Little Lamb" that I have been hearing recently at pub sings, with the rousing chorus:

Hurrah for Mary! Hurrah for the lamb!
Hurrah for the Fenian boys who do not give a damn!
And everywhere that Mary went the lamb was sure to go,
Shouting the battle cry of freedom.

After the usual verses, it goes on:

Mary had a little lamb.
It had a sooty foot,
And everywhere that Mary went,
Its sooty foot it put.

Mary had a little lamb.
Her father shot it dead.
Now Mary takes the lamb to school
Between two hunks of bread.