Greene, H. 1983 25 June (continued) and on for over an hour. At one point I timed the head as moving ~1m in 20 seconds of slow reticular crawl. This was always the predominant mode of locomotion, even when it stretched out completely on a fallen log, except when it ascended over low limbs and once a fallen 55 gal drum. Occasionally if we moved nearby it stopped and turned it's head toward the movement. Twice I poked it's tail firmly w/ a twig, ad it produced a loud noise by vibrating the tail. Saw frequent volleys of tongue flicks, but never long, [illegible] slow ones. ~0730h, just as the Lachesis disappeared in vegetation N. Of the boardwalks at forest edge behind the kitchen, Isidro Chacón called me to see a Tawandura foraging in litter and low limbs at the forest edge. Uniform reddish brown w/ a black saddle. Obvious to me unless I moved or used camera flash. At one point it went ~5m up a small tree quickly, had descended to a 3cm diameter vine and deftly moved horizontally several meters. Tail used frequently. Once it fell from several meters up, but caught a vine w/ one hind foot and the tail ~ 1/2 down