The song you're looking for is called "See-Lye Woman (Sea Lion)" on the album "Field Recordings, Vol. 4: Mississippi & Alabama (1934-1942)" released 1998 on the Document label. There it is sung by Katherine & Christeen Shipp, who sound very young. In fact, the song has the flavor of a girls' jump-rope rhyme with a sort of African beat. In fact, the whole album looks very interesting. You can hear sound samples of all 44 cuts at Yahoo! Music.

By the way, I doubt that African-American girls in Mississippi or Alabama in the 1930s or 40s would be singing about a "sea lion" woman anyway. They seem awfully far removed from the "selkie" legends. And they are definitely pronouncing it "see-lye" or maybe "seal-eye." "Sea lion" sounds like a rationalization to me. Do you suppose the song has been handed down from some African language?

Anyway, the same song, under the title SEE LINE WOMAN, and gussied up a bit to make it sexier, became a hit for Nina Simone, who recorded several versions. I pieced the following together from various sound samples:

See line woman (see line) she drink coffee (see line)
She drink tea (see line) then she go home (see line)
See line woman (see line)

See line woman ... dressed in green ...
Wear silk stockings ... with golden seams ...
See line woman ...

See line woman ... dressed in red ...
Make a man ... lose his head (or "wear a rag ... on her head") ...
See line woman ...

See line woman ... dressed in black ...
Sleep all day ... on her back ...
See line woman ...

[And in what sounds like a studio outtake, I also heard this:]

See line woman ... dressed in white ...
Sleep all day ..., bonk all night ...
See line woman ...