Rivers of Stone, Rivers within Stone

 (Rock Art in Ancient Puerto Rico) – Peter G. Roe

https://www.flickr.com/photos/alan_cressler/15672097522/in/photostream/

https://www.flickr.com/photos/alan_cressler/15050560374/in/set-72157648859509881

“Rock art has eluded quantification, pictographs and petrogylphs tend not to be regarded as fit subjects for “scientific” study. Because of that abdication, many amateurs have rushed in to fill the void, some competent and cautious, others rash and sloppy, reading all sorts of bizarre notions into the “ultimate Rorschach test” that is rock art (page 298).”

http://www.johnpilling.net/living-in-americas-2010-f/Syllabus_2_files/Ancient%20Borinquen-%20Archaeology%20and%20Ethnohistory%20of%20Native%20Puerto%20Rico,%20Peter%20E.%20Siegel-%20editor,%20pages%20285-352.pdf

Isla de Mona: http://islandsofpuertorico.com/isla-de-mona/

http://www.flickriver.com/search/Isla+de+Mona,+Puerto+Rico/interesting/

And then there's this:

 Amateur Rushing In with Bizarre Notions Somewhere in CT: Faces in Stone