PIPER—FLORA OF THE STATE OF WASHINGTON. 
Amelanchier utahensis. 
Artemisia tridentata. 
Artemisia tripartita. 
Chrysothamnus nauseosus. 
Ericameria nana. 
Eriogonum microthecwm. 
Eurotia lanata. 
Grayia spinosa. 
Adenostegia capitata. 
Artemisia dracunculoides. 
Asclepias mexicana, 
Atripler canescens. 
Bergia texanda., 
Carex douglasii. 
Castilleja pallescens. 
Chaenactis douglasii. 
Chorizanthe watsoni. 
Chrysopsis villosa. 
Cleome lutea. 
Coldenia nuttallii. 
Coleosanthus linifolius. 
Comandra pallida, 
Corispermum hyssopifolium, 
Cryptanthe pterocarya, 
Dondia depressa. 
Erigeron concinnus. 
Erigeron divergens. 
Euphorbia glyptosperma. 
Gaertneria acanthicarpa. 
Gaura parviflora. 
Gilia leptomeria, 
Gilia parviflora. 
Gilia pungens hookeri. 
Hymenopappus tenuifolius. 
Iva avillaris. 
Iva xanthifolia. 
Lactuca pulchella. 
Lappula occidentalis. 
Lupinus pusillus. 
Mamillaria sp. 
Mollugo verticillata, 
Monolepis pusilla, 
Nicotiana attenuata. 
Kunzia tridentata. 
Ramona incana. 
Rhus glabra occidentalis. 
Rhus toricodendron. 
Ribes aurewn. 
Ribes cereum. 
Sarcobatus vermiculatus. 
Tetradymia canescens. 
Oreocarya leucophaea. 
Orobanche lidoviciana, 
Orogenia linearifolia. 
Oxrytheca dendroided. 
Pentstemon acuminatus, 
Pentstemon deustus, 
Pentstemon gairdneri, 
Pentstemon glaber. 
Phaca inflexra. 
Phacelia linearis. 
Phlox longifolia. 
Phragmites phragmites. 
Piptocalyx circumscissa. 
Psoralea lanceolata scabra. 
Ptiloria paniculata. 
Ptiloria tenuifolia. 
Rumer venosus. 
Schoenocrambe linifolia. 
Sitanion hystrix. 
Solanum triflorum. 
Sphaeralcea munroana, 
Sporobolus airoides, 
Sporobolus asperifolius. 
Sporobolus cryptandrus. 
Strepltanthus longirostris. 
Stipa bloomeri. 
Stipa comata. 
Stipa occidentalis. 
Stipa thurberiana. 
Thelypodium integrifolium. 
Thelypodium laciniatum. 
Thelypodium nuttatlii. 
Trifolium megacephalum, 
Zygadenus paniculatus. 
39 
From the foregoing lists it is evident that the greater portion of 
the Upper Sonoran flora in Washington is of Great Basin origin. 
The comparatively small proportion of Californian species is prob- 
ably due partly to the barriers through which few plants of this zone 
