1. Bark tight, covered with lenticels; pith white; leaves rarely simple; inflores- 



cence a dichotomous or umbelliform cyme; petals expanding, free 

 from one another, dropping singly; seeds trigonous (2) 



2(1). Cyme dichotomous; flowers 5-merous; disk with entire or crenulate margins 

 2. Ampelopsis 



2. Cyme umbelliform; flowers 4-merous; disk deeply 4-lobed 3. Cissus 



1. Vitis L. Grape 



Deciduous rarely evergreen polygamo-dioecious viny shrubs, climbing by ten- 

 drils; pith brown, interrupted at the nodes by a diaphragm; leaves simple, dentate, 

 mostly rounded and cordate, usually lobed, rarely palmately compound; flowers 

 fragrant, 5-nierous, in a compound thyrse opposite a leaf; sepals minute or obso- 

 lete; petals cohering at the apex and falling as a whole at anthesis; disk hypo- 

 gynous, consisting of 5 nectariferous glands alternate with the stamens; ovary 

 2-celled; cells 2-ovuled; style conical, short; fruit a pulpy 2- to 4-seeded berry; 

 seeds usually pyriform, with a contracted beaklike base, with 2 grooves on the 

 ventral side. 



About 60 species in the Northern Hemisphere, mainly in temperate regions. 



Most wild grapes provide food, protection and nesting sites for birds, and 

 food and cover for wild animals. Both fresh and dried fruits are eaten. The 

 shreddy bark of most species is also used in nest building. 



1. Lower surface of fully grown leaves more or less covered with a permanent 

 indument or (if somewhat naked) either whitened to silvery-bluish- 

 green, covered with both short and long cobwebby hairs con- 

 tinuous or in patches (floccose) lying parallel to the surface; 

 younger shoots, petioles and peduncles thinly to densely woolly 

 or pubescent (2) 



1. Lower surface of fully grown leaves (except usually the veins) green and 



glabrous or rarely with short straight hairs erect-spreading from 

 surface; younger shoots, petioles and peduncles glabrous or thinly 

 woolly or with short erect-spreading hairs (3) 



2(1). Leaves of flowering shoots unlobed or shallowly lobed with the lobes 

 toothed to the base; lower surface of leaves dull-green with a more 

 or less uniform continuous (though often thin) covering of gray- 

 ish cobwebby hairs 1. V. cinerea. 



2. Leaves of flowering shoots shallowly or deeply lobed, the deeply lobed ones 



with entire sinuses; lower surface of leaves usually with grayish or 

 reddish-brown cobwebby hairs, sometimes blue-glaucous and thinly 

 hairy 2. V. aestivalis. 



3(1 ). Leaves (at least some) deeply lobed (4) 



3. Leaves entire or (at most) shallowly lobed (5) 



4(3). Axis of inflorescence sparsely and loosely long-pubescent or glabrous; fruit 



gray-bluish and glaucous; margins of leaves often ciliolate 



3. V. riparia. 



4. Axis of inflorescence densely short-pubescent; fruit black, not glaucous; margins 



of leaves scarcely or not at all ciliolate 4. V. palmata. 



5(3). Distribution in mountains of Trans-Pecos Texas and westward 



5. V. arizonica. 



5. Distribution in eastern third of Texas 6. V. vulpina. 



1. Vitis cinerea Engelm. Graybark grape, sweet grape, parra silvestre. 



Lax high-climbing vine; growing tips and branchlets angled, permanently close- 

 pubescent with ashy-white or gray hairs; diaphragm 3-5 mm. thick; stipules 2-4 

 mm. long; leaves of fertile branches suborbicular to broadly ovate, with a prolonged 



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