KEY TO THE SPECIES 17 



XIV. ULMACEiE (Elm Family) 



Trees with alternate serrate pinnately veined leaves, 4-9- 

 cleft calyx, no petals, 4-9 stamens, 2 styles, and a 1-3-celled 

 ovary becoming a winged or berry-like fruit. 



1. CELTIS (Hackberry) 



Small or large trees with pointed petloled leaves, greenish axillary flowers 

 appearing with the leaves, and fruit fleshy, inclosing a stone (drupe). 



1. Celtis occidentalls L. Leaves reticulate, heart-shaped, ovate, or lanceo- 

 late, taper-pointed, sharply serrate ; fruit reddish or yellowish, becoming dark 

 purple, as large as small cherries, sweet, edible. Woods and river banks. Rare in 

 this range. 



XV. MORACEiE (Mulbekey Family) 



Trees, shrubs, or herbs (our only native genus an herbaceous 

 vine) ; calyx 5-parted ; petals none ; stamens 5 ; ovary superior, 

 1-celled. 



1. HUMULUS (Hop) 



A rough twining vine, climbing to a height of several meters ; leaves large, 

 opposite, palmately veined, petloled and stipulate ; flowers dioecious, the staminate 

 panicled, the pistillate in clustered aments ; bracts leafy, each 8-flowered ; akene 

 invested with the enlarged scale -like calyx. 



1. Humulus lupulus L. (Hop). Leaves broadly ovate in outline, deeply 

 3-7-clef t ; the ripe fruits (hops) 2-4 cm. long, sprinkled with yellow resinous grains, 

 as is also the calyx. 



XVI. SANTALACEiE (Sandalwood Family) 



Herbs or shrubs ; leaves alternate, without stipules ; flowers 

 perfect, the calyx 3-5-cleft and adherent to the ovary ; stamens 

 as many as the calyx lobes ; fruit a nut-like drupe. 



1. COMANDRA (Comandra) 



Smooth perennial herbs, probably parasitic on the roots of other plants ; 

 leaves pinnl-veined, alternate ; flowers bractless, in terminal umbel-like cymes ; 

 calyx bell-shaped ; fruit globose, surmounted by the persistent calyx. 



1. Comandra pallida A. DC. (Pale Cohandra). Erect, 1-2 dm. high, the 

 stems arising from horizontal rootstocks ; leaves pale and glaucous, linear to 

 lanceolate or oblong ; cymes corymbose, several-flowered ; calyx greenish-white 

 or purplish ; fruit becoming dry and hard, 5-7 mm. in diameter. Abundant on 

 sandy open or partly wooded slopes and in the draws. 



