ILLUSTRATIONS. 



PLATES. 



Facing page. 



Plate 46. View at Nogales, showing scanty vegetation 292 



47. View at Nogales, showing bear grass (Nolina) and scrub oaks 292 



48. Yucca brevifolia and an oak at Nogales 293 



49. Cowania stansburiana, a characteristic desert shrub at Nogales 293 



50. Echeveria gloriosa Rose - • - 295 



51. Echeveria gloriosa Rose - - - 295 



52. Graplopetalum pusillum Rose - - - 29G 



53. Sedum compactum Rose 297 



54. Sedum farinosum Rose - 297 



55. Sedum humifusum Rose 298 



56. Sedum liebmannianum Ilemsl 299 



57. Sedum mellitulum Rose 299 



58. Sedum pachyphylliim Rose - 299 



59. Sedum rhodocarpum Rose 300 



60. Sedum treleasei Rose - - 300 



61. Pachyphytum compaction Rose - 301 



62. Ariocarpus fissuratus (Engelm.) Schum 308 



63. Ariocarpus lloydii Rose 308 



64. Opuntia ballii Rose - - - 309 



65. Opuntia deamii Rose - - - - 309 



66. Opuntia eichlamii Rose - 310 



67. Opuntia mackensenii Rose 310 



FIGURE. 



Tage. 



Figure 55. Graplopetalum pusillum 296 



VII 



