Flowering stems at Organ Pipe Cactus National Monument, 2/25/05.
Plants in flower near The Chimneys at Big Bend National Park, 3/23/06.
Plant habit with leaves on A Mountain on the east side of Las Cruces, 10/15/05.
Young stem showing spine development on A Mountain 10/2/05. Having the spines formed of half of the petioles of otherwise green & photosynthetic leaves is unique to the family.