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UNIVERSITY OF MISSOURI STUDIES 



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bunch-grasses occupy the ground. The two species of im- 

 portance are Yucca glauca and Eriocoma cuspidata. 



d. Sylvestres. A good example of the wooded mesa 

 lies immediately back of the Chautauqua grounds. There the 

 bull pine has descended from the foot-hills and taken posses- 

 sion of the mesa. Besides the bull pine, Pinus scopulorum, 

 the low juniper, Jimiperus Sibirica, is of rare occurrence. 

 Of herbs the most noteworthy is Arnica pedunculata, which 

 is frequent under the pines. I found also only there Ccntun- 

 culus minimus, perhaps the only known station of this plant in 

 Colorado, since it is not included in Rydberg's Flora of Colo- 

 rado. It is growing with Linaria Canadensis, which is like- 

 wise an eastern plant. 



e. Arbustales. The brush mesa assumes various forms. 

 Ordinarily some one species is in control. Occasionally it con- 

 sists of various haws, as at the entrance of Gregory Cafion, 

 or of a thicket of juneberries, wax-currants, and skunk-bushes. 

 South of Bluebell Canon is a mesa covered with the peculiar 

 mountain mahogany. Wild cherries and plums are frequent, 

 and the hackberry occasional in these shrubby thickets. The 

 principal species are : 



Celtis reticulata 

 Ribes pumilum 

 R. longi folium 

 Oreobatus deliciosus 

 Batidaea laetissima 

 Cercocarpus parvifolium 

 Rosa Sayi 



Amelanchier oreophila 

 Crataegus occidentalis 

 C. Coloradensis 



C. erythropoda 

 Prunus Americana 

 P. melanocarpa 

 Toxicodendron Rydbergii 

 Schmaltzia trilobata 

 Ceanothus Fendleri 

 C. mollissimus 

 C. subsericeus 

 Symphoricarpos occidentalis 



