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



Key to the genera 



1. Leaves simple, often shallowly lobed; petals partly united and connivent at 



an thesis 1. Vitis. 



1. Leaves compound or very deeply lobed; petals separate and spreading at 

 anthesis (2). 

 2. Leaves digitately 5- to 7-foliolate, relatively thin, deciduous; flowers 5- 



merous 2. Parthenocissus. 



2. Leaves deeply 3-lobed to 3-foliolate, thick, persistent; flowers 4-merous. 



3. Cissus. 

 1. VITIS. Grape 



Stems climbing or trailing; leaves large, with rounded, cordate, 

 often shallowly lobed blades, persistently pubescent or glabrate; 

 flowers rarely perfect; petals more or less coherent at apex until they 

 fall; berries globose or nearly so, juicy, few-seeded. 



1. Vitis arizonica Engelm., Amer. Nat. 2: 321. 1868. 



Coconino County and Hualpai Mountain (Mohave County), to 

 Greenlee, Cochise, and Pima Counties, 2,000 to 7,000 feet, common 

 along streams and in canyons, often climbing on trees, April to July. 

 Western Texas to southern Utah, Arizona, and northern M exico. 



Canyon grape. The berries are of good quality for jelly and grape- 

 juice and are much eaten by birds. They are also eaten, both fresh 

 and dried, by the Indians. The vines are useful in checking soil 

 erosion along creeks. The leaves when chewed allay thirst. In 

 addition to the typical form, with permanently more or less pubescent 

 leaves, a glabrate form, var. glabra Munson, occurs throughout the 

 range of the species in Arizona. Specimens with leaves more deeply 

 and irregularly toothed than is usual, collected in Chevelon Canyon, 

 Navajo or Coconino County {Zuck in 1896), and near Flagstaff {Mun- 

 son and Hopkins in 1889) , ma} 7 be V. treleasei Munson but do not appear 

 to be specifically distinct from V. arizonica. An exceptionallv 

 pubescent form was collected near Lake Mead, Mohave Countv 

 {Clover 4294). 



2. PARTHENOCISSUS. Virginia-creeper 



Stems mostly trailing; tendrils often expanded at apex into disk-, 

 that adhere to bark or other surfaces; leaves large, digitately com- 

 pound, the leaflets 5 to 7, deciduous; flowers 5-merous, the petals 

 spreading at anthesis; berries thin-fleshed; seeds 1 to 4. 



1. Parthenocissus vitacea (Knerr) A. S. Hitchc, Spring Fl. Man- 

 hattan 26. 1894. 



Parthenocissus quinquefolia (L.) Planch, var. vitacea Knerr, 

 Bot. Gaz. 18: 71. 1893. 



Apache County to Coconino County, south to Cochise and Pima 

 Counties, 4,000 to 7,000 feet, May to September. Ohio to Wyoming, 

 New Mexico, and Arizona. 



Very similar to the Virginia-creeper {P. quinquefolia) of the eastern 

 United States, which is often cultivated as an ornamental climbing 

 plant. The handsome foliage is beautifully colored in autumn. 



3. CISSUS 



Stems trailing or clambering, from large tubers; leaves digitately 

 3-foliolate or deeply 3-lobed, somewhat fleshy, persistent; flower parts 



