Hendrickson 1950 Journal Nov. 18 Villavicencio, Meta, to Trinidad, Boyaca, Colombia, S.A. the "sural" formation; he says the hummocks of are raised about 20'-30". He knows of no accepted explanation for the method of formation of the "sural"; he says he is inclined to believe it is due to erosion between the areas of soil held by the grass roots. Deer (usually small groups) were seen several times by Dr. Stebbins and Torriente Castillo; I missed a glimpse of them each time (they were out on the open llanos). I noted one large (4'-4'1/2 wing spread) heron with black primaries and secondaries, white head, neck, and shoulders. I also saw two "Rey gallinazo" (king civures). N. of Rio Cravo dur we flew over a somewhat drier-looking area of the llanos. Here I saw one stream (unique among those seen here so far) which had cut its bed down into a canyon which looked about 50 ft. deep (Caño Guirrija?). N. of this canyon the llanos again began to appear wetter. As an index possible to the depth of the ponds in the llanos of this region, Dr. Stebbins reports one cow seen standing in the middle of