520 INDEX. 



Page. 



Pifion, Mexican 37 



single-leaf 37 



Pinus arizonica 38 



cembroides 37 



ehihuahnana 39 



coulteri 39 



edulis 37 



mayriana 38 



monophylla 37 



ponderosa 38 



sabiniana 39 



strobifonnis 36 



torreyana 3s 



Pitahaya " 65, 66 



dulce » 66 



Plains mouse, ( 'hihuahua 389 



San Diego 398 



Sonora. 384 



Wester.n I teserl 39 I 



Plants gathered by the Internal ional Boundary Commission L30 



Platanns occidentalis 56 



racemosa ' r >(> 



wright i 56 



Playas valleys LI, 15 



Populus angusti folia 47 



fremontii 48 



tremuloides 47 



wislizeni 48 



Post Spring, Fort Huachuca 102 



Pozo de Luis, Mexico 18, 19, 114, 115 



flora of ' L15 



Pozo Verde 113 



Mountains 113 



Prairie-dog, Arizona 340 



short-tailed 345 



Pride of India 69 



Prong-horn. Mexican 221 



Prong-horns 220 



Prosopis glandulosa 59 



odorata 59 



velutina 60 



Primus demissa 58 



ilicifolia 58 



integrifolia 58 



salicifolia 58 



Pseudotsuga mucronata 39 



Ptelia betulifolia 62 



cognata 62 



jucunda 62 



saneta 62 



trifoliata 62 



Puga, Guillermo B. y, International Boundary Commissioner 1 



Quaking asp 47 



