Ancient fertility symbol from the island of Moloka'i.
The legend is that Kawahuna, the wife of Nanahoa, a noted chief, found him admiring another woman. In anger at her jealousy, Nanahoa threw Kawahuna down the hill, but both Nanahoa and Kawahuna turned to stone. It is said that if a barren woman spends the night near this sacred pohaku (stone), she will become pregnant.
The stone stands about ten feet high, and is partially a natural formation, partially carved.
I've posted a snapshot of an albumen version from this negative here (post #19)--
http://www.apug.org/forums/showthread.php?t=27342&page=2
(Print photographed with a Coolpix 990 on a copy stand, for those who are checking the exif data)
[edit:--Oops, looks like I caught a reflection off the glass (this is a framed print) in the upper right corner, which I didn't see on my monitor at home. My copy stand is right near a window, and I forgot to close the shade. I'll post another one tonight or tomorrow, when I get a chance.]