152 WYETHIA ARIZONICA. ARIZONIAN WYETHIA. 



But it was not on this part of the journey that the Wyethia 

 was discovered, but on the return trip to the Missouri of Wyeth's 

 party. Knowing nothing of botany, yet Mr. Nuttall's love of 

 collecting had so impressed Wyeth that he determined to collect 

 himself, and this was among the lot he found. Mr. Nuttall sub- 

 sequendy described it in the "Journal of the Academy of Natural 

 Sciences of Philadelphia" as Wyethia hclianthoides. The loca- 

 tion given was the "Kansas plains, near the Flat Head River, 

 towards the sources of the Oregon." Since that time nine other 

 species have been found, and there may probably be more by 

 the time the interior of our country has been fully explored. 



The first impression of the collector w^ould be to compare it 

 with the sun-flower — HdiantJms — and this evidendy was Mr. 

 Nuttall's idea in the name of his first species — W. helian- 

 tJioidcs; but a critical examination of the flowers will show the 

 distinction. The tube of the disc corolla (see Fig. 4) is campan- 

 ulate, and with very litde constriction at the point of union wdth 

 the achene. 



Since the above w^as written. Dr. Rothrock's " Botany of the 

 Wheeler Survey of the One Hundredth Meridian" has appeared, 

 in which is a good plain drawing and description of the plant, which 

 was found by the collectors at Willow Spring, Arizona. There 

 are som^e litde differences between the plant found here and the 

 descripdon adopted at the head of our chapter. Rothrock found 

 the plant two or three feet high, and from two to four flowered, 

 and the flowers are rather large instead of " small." There are 

 also some slight differences in the details of the flowers. It is 

 well to call attention to these litde differences as showing the 

 student that he must rarely expect to find a plant in any species 

 to agree exacdy with a description in every litde particular. 

 Variation, as a law of nature, pervades the individuals of a spe- 

 cies, as well as gives the character to species itself. 



