196 MISC. PUBLICATION 423, U. S. DEPT. OF AGRICULTURE 



4. Calochortus ambiguus (M. E. Jones) Ownbey, Mo. Bot. Gard. 



Ann. 27:505. 1940. 



Calochortus watsoni var. ambiguus M. E. Jones, Contrib. West. 

 Bot. 14: 27. 1912. 



Northern Coconino County and eastern Mohave County, south to 

 southern Navajo, Cochise, Santa Cruz, and Pima Counties, 3,000 to 

 8,000 feet, dry slopes, chaparral, and open pine forests, April to August. 

 New Mexico and Arizona. 



The most widely distributed and generally the most abundant of 

 the Arizona mariposas, closely resembling C. nuttallii in general ap- 

 pearance. 



5. Calochortus gunnisonii S. Wats, in King, Geol. Expl. 40th Par. 5: 



348. 1871. 

 Keet Seel (northern Navajo County) and White Mountains (Apache 

 County), 6,500 to 8,000 feet, June to August. Western South Dakota 

 and Montana to New Mexico and northeastern Arizona. 



14. YUCCA. 23 SOAPWEED, SPANISH-BAYONET, DATIL 



Large plants with a thick, branching, mainly subterranean caudex 

 or a distinct trunk above ground; leaves numerous, clustered a^ the 

 ends of the branches, narrow, elongate, commonly spine-tipped; 

 flowers large, perfect, numerous or many in terminal racemes or pan- 

 icles; perianth segments rather thick, whitish; ovary 3-celled; fruit 

 dry or fleshy; seeds many, flat. 



The yuccas are an important resource of the Indians of the South- 

 west. The buds, flowers, and emerging flower stalks are eaten raw 

 or boiled, or the last roasted like mescal. The large pulpy fruits of 

 the baccate species (Y. baccata, etc.) are eaten raw or roasted, dried 

 for winter use, or ground into meal, and the seeds also are used for 

 food. A fermented beverage was made from these fruits. Fiber 

 from the leaves furnishes material for rope, mats, sandals, baskets, 

 and cloth. The roots, known as amole, have saponifying properties 

 and are used as a sort of soap and as a laxative. The seeds are the 

 natural food of the larvae of small moths, winch pollinate the flowers 

 by gathering the pollen into a mass that is pushed into the tube of the 

 stigma. 



Key to the species 



1. Fruit dehiscent, thin walled, dry (2). 

 2. Inflorescence racemiform (3). 



3. Peduncle short, not exceeding the leaves 2. Y. baileti. 



3. Peduncle longer than the leaves 3. Y. angustissima. 



2. Inflorescence amply paniculate; peduncle greatly exceeding the foliage (4). 



4. Leaves denticulate, 8 to 15 (occasionally 20) mm. wide; plant acaulescent 



or nearly so; style slender; stigma capitate 1. Y. whipplei. 



4. Leaves filiferous on the margins, 4 to 10 (rarely 13) mm. wide; plant 

 caulescent, 1 to 4 meters high; style stout; stigma not capitate. 



4. Y. elata. 

 1. Fruit indehiscent, fleshy or spongy (5). 



5. Leaves denticulate, very rigid; plant arborescent; branches repeatedly fork- 

 ing to form a spreading crown 5. Y. brevifolia. 



23 References: Trelease, W. the yucceae. Mo. Bot. Gard. Ann. Rpt. 13. 1902. 



McKelvey, S. D. yuccas of the southwestern united states i. 1938. 



The writers are indebted to Mrs. McKelvey for identifying many of their specimens. 



