CONTRIBUTIONS TO WESTERN BOTANY. 70I 



Encelia nudicaiiUs Gray. 



Helianthella nudicazilis Gray. 



No. 5069k. April 17, near Horse Spring, Arizona, 

 2500° alt., in compact clay, on a bare and rather alkaline 

 knoll, in poor soil. 



No. 5376. June 2, Marysvale, Utah, on loose talus, in 

 very dry and hot places, volcanic soil, 6500° alt. 



No. 5095ak. April 23, top of grade, four miles above 

 Pagumpa, Arizona, on barren clay slope, in juniper belt. 



An examination of the type specimen of this species 

 shows that it is not the same as E . m'gophylla. All the 

 specimens described by me in Zoe, iii, 304, belong to this 

 species, apparently, or else there are two species included 

 in this one. It is very probable that this will prove to be 

 an exceedingly variable species, having a wide range. 

 The northern plants which I have described in Zoe have 

 a very different habitat, since they grow on dry and rocky 

 ridges, in very exposed situations, where the soil is free 

 from alkali. On the other hand, all the specimens given 

 above under this species flourish in an alkaline, clayey soil, 

 where no other plants will grow. The allied species, E . 

 argophylla, I have never seen anywhere except in very 

 salty soil, along the salt deposits of eastern Nevada, in 

 the Larrea belt. It appears that it is never found grow- 

 ing in any other situations. 



An examination of nearly all the species of Encelia 

 shows that the character of wingless akenes separating 

 this from Verbesina is not good, as several species, such as 

 E . eriophylla, E. viscida, etc., have corky wings. In E . 

 nutans Eastwood, which is probably the same as, or a 

 variety of, Verbesina scaposa Jones, though rayless, the 

 outer disk akenes are triquetrous and winged, and doubt- 

 less represent ray flowers; the species was, therefore, 

 properly placed in that genus with winged akenes, though 

 the habit is that of Encelia. 



