FAGACEAE. 99 



9. Quercus Fendleri Liebm. A shrub, 1-3 m. high, growing on dry hillsides 

 from Colo, to Tex. and Ariz. Alt. 5000-7000 ft. Mesas near Colorado 

 Springs; McElmo Canon; Raton Mountains, near Trinidad; Canon of Ar- 

 kansas; Green Horn Mountains; Poncho Pass; Purgatory River, near 

 Trinidad. 



10. Quercus pungens Liebm. (Q. undulata Wrightii Engelm.) A low 

 shrub, 1-3 m. high, on dry hills from Colo, to Utah, Tex. and Ariz.; also 

 Mex. Canon City; Arkansas Canon. 



11. Quercus undulata Torr. (Q. undulata Jamesii Engelm.) A shrub, 1-3 

 m. high, growing on dry hills from Colo, to Tex. and Ariz. " Rocky Moun- 

 tains " ; Canon of the Arkansas ; Steamboat Springs. 



Order 21. URTICALES. 



Style and stigma i ; ovules erect or ascending ; herbs with small greenish flowers ; 



fruit an achene. 39. URTICACEAE. 



Styles and stigmas 2 ; ovules pendulous. 



Herbs or herbacious vines with opposite leaves ; fruit an achene. 



40. CANNABINACEAE. 

 Trees or shrubs with alternate leaves ; fruit a samara or drupe. 



41. ULMACEAE. 



Family 39. URTICACEAE Reichenb. NETTLE FAMILY. 



Herbs with stinging hairs ; leaves opposite ; flowers not involucrate. 



i. URTICA. 



Herbs without stinging hairs ; leaves alternate ; flowers involucrate by leafy 

 bracts. 2. PARIETARIA. 



i. URTICA L. NETTLE. 



Teeth of the leaves ovate, strongly directed forward ; stem sparingly strigose 



and bristly. i. U. gracilis. 



Teeth of the leaves broadly triangular, not strongly directed forward ; stem 



glabrous or nearly so. 2. U. gracilenta. 



1. Urtica gracilis Ait. In alluvial soil along streams from N. S. to Alaska, 

 N. C. and N. M. Alt. 4000-9000 ft. Mountains between Sunshine and Ward ; 

 Steamboat Springs; Mancos; Bob Creek, West La Plata Mountains; Fort 

 Collins; along the Uncompahgre River, near Ouray; chaparral-covered hills 

 southeast of Ouray; Gunnison; Spring Canon; Campton's ranch. 



2. Urtica gracilenta Greene. (U. Breweri Coulter; not S. Wats.) Along 

 streams from Wyo. to Tex. and N. M. Alt. up to 9000 ft. Near Pagosa 

 Peak. 



2. PARIETARIA L. PELLITORY. 



Leaf-blades lanceolate, 2-7 cm. long, twice as long as the petioles or longer. 



i. P. pennsyhanica. 



Leaf-blades oblong or ovate-oblong, 0.5-2 cm. long, not twice as long as the 

 petioles. 2. P. obtusa. 



i. Parietaria pennsylvanica Muhl. On shaded banks and hillsides from 

 Dnt. to B. C., Fla. and Mex. Alt. 4000-7000 ft. Steamboat Springs; Lower 

 Boulder Canon, Boulder Co. ; Black Canon ; foot-hills, Larimer Co. ; gulch 

 west of Pennock's mountain ranch; along Poudre River, near Fort Collins; 

 Horsetooth Gulch. 



