The rhyme scheme in this excerpt from Longfellow's "The Tide Rises, the Tide Falls" is A. aabba.
A stands for the words falls, calls, and in the end, falls again. B stands for brown and town, which rhyme as well. There is no C in the rhyme, because there are only two sounds that rhyme, the first, second, and last line sound the same, and the third and fourth line also sound the same.