It seems that there were these 3 pregnant Indian Squaws, all due to give
birth at about the same time.  The first squaw gave birth to a boy, and the
birthing was done on a deer hide.  The 2nd also gave birth to a boy, but this
was done on a bear hide.  And, the third had twins, two boys, and
she did this on a hippopotamus hide.

This means that the sons of the squaw on the hippopotamus hide
is equal to the sons of the squaws on the other two hides.