814 MISC. PUBLICATION 42 3, U. S. DEPT. OF AGRICULTURE 



Dakota and eastern Montana to Kansas, New Mexico, and northern 

 Arizona. 



The Arizona form is subsp. venosus Keck, type from 12 miles north- 

 east of Tuba, Coconino County (Peebles and Fulton 11877), found also 

 in southern Utah and northwestern New Mexico. This is the western- 

 most representative of the variable P. angustifolius, which, in typical 

 form, grows on the high plains east of the Continental Divide. This 

 is replaced in southeastern Colorado, Kansas, and northern New 

 Mexico by subsp. caudatus (Heller) Keck (P. caudatus Heller), which 

 intergrades completely with typical P. angustifolius. The Arizona 

 form, subsp. venosus, is closely related to subsp. caudatus but is 

 distinguished by pinkish-lavender instead of blue flowers, herbage 

 not darkening appreciably in drying, and bracts of the inflorescence 

 more prominently venose on both sides. The Hopi Indians are 

 reputed to make a medicine of the roots and call the plant "tci-eq-pi," 

 meaning snake plant. 



22. Penstemon lentus Pennell, Contrib. U. S. Natl. Herbarium 20: 



359. 1920. 

 Apache County, hi the Lukachukai Mountains (Goodman and Pay- 

 son 2882) and at Fort Defiance (E. Palmer 100), 6,000 to 8,700 feet, 

 very rare, dry hills and mesas, usually in sandy soil, June. South- 

 western Colorado, southeastern Utah, and northeastern Arizona. 



23. Penstemon thompsoniae (A. Gray) Rvdb., TorreyBot. Club Bui. 



36: 690. 1909. 



Penstemon pumilus Nutt. var. thompsoniae A. Gray, Syn. 

 F1.2 1 : 269. 1878. 



Kaibab Plateau and southward (Navajo, Coconino, Mohave, and 

 Yavapai Counties), 4,800 to 7,000 feet, light soils with pinyon and 

 juniper, May to June. Southern Utah, southeastern Nevada, and 

 northern Arizona. 



24. Penstemon caespitosus Nutt. ex. A. Gray, Amer. Acad. Arts 



and Sci. Proc, 6: 66. 1862. 



Painted Desert and Grand Canyon regions (Navajo and Coconino 

 Counties), 4,500 to 7,000 feet, sometimes on limestone soils, June to 

 August. Wyoming, Colorado, Utah, and northern Arizona. 



This variable species, which comprises some of the smallest known 

 plants in the genus, is represented in Arizona by subsp, desertipicti 

 (A. Nels.) Keck (P. desertipicti A. Nels., type from near Cameron, 

 Coconino County, Hanson A177). 



25. Penstemon oliganthus Woot. and Standi., Contrib. U. S. Natl. 



Herbarium 16: 172. 1913. 



White Mountains (Apache County), 8,000 to 9,000 feet, loamy 

 soil, July and August. Colorado, New Mexico, and eastern Arizona. 



A low herb with few stems arising from small rosettes, the flowers 

 often somewhat declined. 



26. Penstemon albomarginatus M. E. Jones, Contrib. West. Bot. 



12: 61. 1908. 

 Near Yucca (Mohave County), 1,500 to 1,800 feet, rare, April 

 and May. Southern Nevada, western Arizona, and eastern Cali- 

 fornia, 



