solanacejE 561 



yellow (S. roslratum, sand bur), or purple iS. dulcamara). 

 The calyx is bell-shaped or rotate, generally live-parted or 

 fiye-pleft. The corolla is rotate or rarely broadly bell- 

 shaped, the tube very short, the limb plaited, five-angled or 

 five-lobed. There are five stamens inserted on the throat of 

 the corolla (Fig. 232); the filaments are short, the anthers 

 converge around the style, and are usually dehiscent by a 

 terminal pore, sometimes by a short introrse terminal slit, 

 and sometimes longitudinally. The ovary is superior, usu- 

 ally two-celled; its style is slender and simple, and the 

 stigma terminal. 



Fruit. — The fruit is a many-seeded berry; the calyx is 

 persistent at the base, and in some species (5. roslratum) 

 encloses the berry. 



Geographical. — There are about 900 species of Solatium, widely distributed, 

 but most abundant in tropical America. 



Key to Important Species of Solanum 



Not tuber-bearing. 



Plant not prickly or spiny. 

 Erect herbs or shrubs. 



Fruit ovoid or egg-shaped, yellow with purple or violet streaks or 

 splashes, often 4 to 6 inches long, S. muricatum (pepino, melon 

 pear). 

 Fruit a small, spherical berry, not over i inch in diameter. 

 Peduncles one- to three-flowered; ripe berries green, S. trifiorum 



(wild tomato, cut-leaved nightshade). 

 Peduncles bearing small cymes, three- to ten- flowered; ripe berries 

 black, S. nigrum (black or common nightshade). 

 Climbing vines, 5. dulcamara (blue bindweed, bittersweet). 

 Plant prickly or spiny. 



Berry not enclosed by the calyx. 

 Flowers light blue or white; fruit a small spherical berry, S. carolinense 



(horse-nettle). 

 Flowers purplish; fruit large, 5. melongena (egg plant). 

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