332 IOWA ACADEMY OF SCIENCE 



Plantago purshii Roem. & Schult. Very abundant in the more 

 arid parts, sometimes imparting a gray appearance to 

 large areas of ground. 



Galium aperine L. In one place along the Umatilla. 



Sambwcus glauca, Xutt. In one place along the Umatilla. 



Vahriaix lla macrocera (T. & G.) Gray. In one or two places 

 in slightly moist ground near the Columbia. 



Dipsacus sylvestris Mill. "Well established but not common 

 along the Umatilla. 



Cichorium intybus L. In cultivated ground; scarce. 



Ptiloria paniculata (Nutt.) Greene. Common in moderately 



dry ground. 

 Symphoricarpos racemosus Michx. In one or two places near 



the Umatilla. 

 Agoseris lieteropliylla (Xutt.) Greene. Scarce, in moist places. 

 Taraxacum taraxacum (L.) Karst. Frequent, in damp ground. 



Lactuca scariola integrator (Gren.) Godr. Very abundant, espe- 

 cially in rather dry ground along the Columbia. 



Lactuca pulchella (Pursh) D. C. Scarce, along the Columbia. 



Sonchus asper (L.) Hill. Frequent, in moist ground. 



Iva axillaris Pursh. Abundant in slightly moist, often alka- 

 line ground along the Columbia and Umatilla. 



Xanthium speciosum Kearn. Common along the Columbia and 

 Umatilla. 



Xanthium oligacanthus Piper. Scarce, along the Umatilla. 

 A curious species, seemingly of very limited distribu- 

 tion. 



Gaertneria acanthicarpa (Hook.) Britt. Very plentiful in 

 moderately dry ground. 



Grmdelia nana Nutt. Common along the Columbia. 



Chrysopsis cillom (Pursh) Nutt. Along the Columbia; rather 

 scarce. 



Chrysothamnus viscidiflorus (Hook.) Nutt. The most abundant 

 of the shrubby Composite ; to be regarded as the dominant 

 desert species. Almost universally present, and only oc- 

 casionally yielding precedence to any other form. 



