1965 AHH Journal
10 Oct. (p.2) E. Potrillo and Mount Riley (?) Latter group of peaks appear to be volcanic; the E. Potrillo sedimentary (including at least limestone). Just west of a gate, a side road south into the mountains. Drove in a mile or so--road goes further. Junipers on slopes and one in the open canyon that the road follows. Ocotillo, Dasylirion, barrel cactus, Mammilaria, Opuntia, creosote bush, Mesquite, Apache Plume. Returned home and in afternoon (2 pm) drove alone west via Country Rd. to NM 273, N about a mile, then west on the Strauss road to the rim of the Rio Grande Valley. Walk north from the base of the valley wall, examining ground for fossil bone. Considerable number of bone frag's. In first areas checked, signs of removal of sand (?), etc. Picked up several frag's of horse in grayish area a short distance (1-3 vertical ft) above a reddish silt stratum. Bone scraps considerably higher also. Continued northerly checking outlying hills of the reddish silt (a series running out to the east)--a scrap or two of bone in the silts, but relatively little. Then climbed above (west) and slightly north of this line of exposures--began picking up bone scraps above the silts, these becoming common where
