514 MISC. PUBLICATION 4 2 3, U. S. DEPT. OF AGRICULTURE 



2. Kallstroemia parviflora Norton, Mo. Bot. Gard. Ann. Rpt. 9: 153 



1898. 



Kallstroemia laetevirens Thornber ex Woot. and Standi., Contrib 

 U. S. Natl. Herbarium 16: 143. 1913. 



Navajo County to Mohave County, south to Cochise, Santa Cruz, 

 and Pima Counties, 2,000 to 5,000 feet, plains and mesas, August to 

 October. Mississippi to Arizona and northern Mexico. 



3. Kallstroemia hirsutissima Vail in Small, Fl. Southeast. U. S. 670 



1903. 

 Cochise County, at San Bernardino Ranch (Mearns 597) and Ben- 

 son (Harrison 8227), Santa Cruz County, near Elgin, (Peebles'et al. 

 3449) 3,500 to 4,700 feet, apparently rare, August to October. Kansas 

 and Colorado to Texas, southeastern Arizona, and northern Mexico. 



4. Kallstroemia californica (S. Wats.) Vail, Torrey Bot. Club Bui 22- 



230. 1895. 



Tribulus calif ornicus S. Wats., Amer. Acad. Arts and Sci 

 Proc. 11: 125. 1876. 



Apache and Yavapai Counties to Santa Cruz, Pima, and Yuma 

 Counties, 5,000 feet or (usually) lower, plains and mesas, commonly 

 in sandy soil, May to October. Southern Colorado to Arizona, 

 southeastern California, and Mexico. 



The typical form, commonly with 4 to 7 pairs of leaflets and rela- 

 tively elevated and sharp dorsal tubercles on the carpels, seems to 

 be confined to the southern part of the State, from Graham County 

 to Yuma County. In the northeastern and central portions, the 

 prevailing form is var. brachystylis (Vail) Kearney and Peebles (K. 

 brachystylis Vail) , with only 3 to 5 pairs of leaflets and lower, blunter 

 dorsal tubercles. There is, however, much intergradation. 



59. RUTACEAE. Rue family 



Plants large shrubs or small trees to nearly herbaceous, more or less 

 strong scented; herbage glandular-punctate; leaves simple or digi- 

 tately compound; flowers perfect or unisexual, regular; sepals and 

 petals commonly 4 or 5, the stamens as many or twice as many; 

 fruit various. 



The most important members of this family, from an economic 

 standpoint, are the citrus fruits — orange, grapefruit, and lemon. 



Key to the genera 



1. Leaves simple, linear or narrowly spatulate; petals erect; fruit a deeply 2-lobed 

 capsule; ovules 5 or more in each carpel; plants small shrubs or nearly 



herbaceous 2. Thamnosma. 



1. Leaves digitately compound; petals spreading; fruit not deeply lobed; ovules 

 1 or 2 in each carpel (2) . 

 2. Plants small shrubs; herbage and capsules glandular-pustulate; leaves with 

 usually more than 3 leaflets; petals white; fruit turgid, of 2 or 3 carpels. 



1. Choisya. 



2. Plants large shrubs or small trees; herbage glandular-punctate, not pustulate; 



leaves 3-foliolate, the leaflets lanceolate or broader; petals greenish or 



yellowish; fruit flat, broadly winged, 1- or 2-celled 3. Ptelea. 



