Answers:
       1: Lophophora alberto-vojtechii plant from Europe
       2: Lophophora "caespitosa" clone from Europe (a horticultural williamsii form)
       3: Lophophora diffusa grown from European seeds
       4: Lophophora williamsii var. echinata in habitat in West Texas
       5: Lophophora williamsii var. echinata in habitat in West Texas
       6: Lophophora fricii grown from European seeds
       7: Lophophora jourdaniana horticultural clone from Europe
       8: Lophophora koehresii in habitat in Tamaulipas, Mexico
       9: Lophophora koehresii in habitat in SLP, Mexico
      10: Lophophora williamsii in habitat in Jim Hogg County, Texas
      11: Lophophora williamsii in habitat in Starr County, Texas
      12: Lophophora williamsii in habitat in SLP, Mexico
      13: Lophophora williamsii in habitat in SLP, Mexico
      14: Lophophora diffusa in cultivation
      15: Lophophora williamsii collected in Starr County, Texas
      16: Lophophora williamsii in cultivation