The January 28, 1918 New York Times tells us that the exciting Jungle (and I assume that includes much of the native scenes) were filmed in Brazil, so the two U.S. film locations were only part of the story.
http://www.nytimes.com/movie/review?res ... 946996D6CF" target="_blank" target="_blank
"TARZAN OF THE APES."; Jungle Story Appears in Film Form at the Broadway.
Published: January 28, 1918
"Tarzan of the Apes," which excited considerable interest among the readers of popular-priced fiction several years ago, was shown at the Broadway Theatre last night in film form. Being the story of a primeval man—or, rather, of a man brought up among apes and endowed with many of their abilities—it presents not a few difficulties to the movie maker. All of these have been overcome in the film at the Broadway, and apes swing realistically from bough to bough in the jungle the while lions and leopards seek their prey on the ground below.
Intertwined with the jungle story is a domestic narrative which grows tedious at times, and the expedient of the cutback is resorted to a trifle too freely. All of this is more than compensated for, however, by the stirring scenes of the jungle. A majority of these were photographed in Brazil, and several hundred natives appear before the camera. The picture as a whole, in addition to being interesting, also has a touch of educational value. An actor named Elmo Lincoln meets the difficult requirements of the hero satisfactorily. [End Quote.]
That original film was much longer than what we can see today.
The latest available copy of this film with a newly composed score can be watched at:
http://www.imdb.com/videoplayer/vi3881542169" target="_blank" target="_blank.
A chance to finally see the whole story if you've never seen it before.
Open, general discussion of silent films, personalities and history.