WorldCat.org has the following description:

THE THOUSAND ISLANDS SONG
from "Angel in the Wings"
by Bob Hilliard and Carl Sigman.
New York : Edwin H. Morris & Co., ©1947.

An sample of a recording by Arthur Godfrey has these lyrics:

I left the one I love on one of the Thousand Islands (row, row your boat)
But unfortunately I can't remember which one.
So I row, row, row, row up the River St Lawrence
And I'm hollerin' "Florence,
Oh where can you be?" (Where oh where, where oh where can she be?)

I wouldn't be so lost up here on the thousand....