100 URTICACEAE. 



2. Parietaria obtusa Rydb. In shaded places from Colo, to Utah, Tex. and 

 Calif. Alt. up to 6000 ft. El Paso; Sunset Canon. 



Family 40. CANNABINACEAE Lindl. HEMP FAMILY. 

 i. HUMULUS L. HOPS. 



i. Humulus lupulus neo-mexicanus Cockerell. The native hops of the 

 Rocky Mountain region has deeper divided leaves and more sharply acuminate 

 bracts than the cultivated variety. It grows along streams from Wyo. to 

 Utah, N. M. and Ariz. Alt. 5000-8000 ft. Fort Collins; Colorado Springs; 

 along the Uncompahgre River, near Ouray; Parlin, Gunnison Co.; Walsen- 

 burg; Manitou; canon west of Palmer Lake; along Cache la Poudre River; 

 Poudre Canon. 



Family 41. ULMACEAE Mirbel. ELM FAMILY. 

 i. CELTIS L. HACKBERRY. 



i. Celtis reticulata Torr. (C. occidental Port. & Coult.; not L.) On 

 hillsides, in rocky places, from Tex. to Colo, and Ariz. Alt. 4000-6000 ft. 

 " Colorado," locality not given ; plains and foot-hills near Boulder ; near Os- 

 borne City; Golden; gulch west of Pennock's mountain ranch; foot-hills 6-8 

 miles west of Fort Collins. 



Order 22. SANTALALES. 



Leaves opposite : fruit a berry ; tree-parasites. 42. LORANTHACEAE. 



Leaves alternate : fruit a drupe or nut ; root-parasites or saprophytes. 



43. SANTALACEAE. 



Family 42. LORANTHACEAE D. Don. MISTLETOE FAMILY. 



Anthers 2-celled ; pollen-grains smooth ; berry globose, pulpy and semi-translucent. 



1. PHORADENDRON. 

 Anthers i -celled; pollen spinulose ; berry compressed, fleshy, opaque. 



2. RAZOUMOFSKYA. 



i. PHORADENDRON Nutt. 



i. Phoradendron juniperinum Engelm. Parasitic on species of Sabina from 

 Colo, and Ore. to Tex. and Calif.; also in Mex. Mancos ; Hotchkiss; Pax- 

 ton ranch. 



2. RAZOUMOFSKYA Hoffm. 



Staminate flowers all or nearly all terminal on distinct peduncles, dichotomously 

 paniculate (on Pinus Murray ana, contorta and divaricata). i. R. americana. 

 Staminate flowers nearly all axillary, forming simple or compound spikes. 

 Branches 12 mm. in diameter. 



Plant yellowish-green ; accessory branches of fruiting specimens flower- 

 bearing. 



Spikes short, 3-5-flowered ; stems bluntly angled (on Pseudotsuga mucro- 

 nata). 



2. R. Douglasii. 

 Spikes many-flowered; stems sharply angled (on Pinus flexilis). 



3. R. cyanocarpa. 



