APRIL 19, 1921 safford: synopsis of datura 175 



5, perfect, adnate to the inner surface of the tube at the middle or near the 

 base, shghtly or not at all exserted, the filaments slender and thread-like, tlie 

 anthers linear, free or rarely cohering, the anther-cells parallel, longitudinally- 

 dehiscent. Ovary 2-celled (sometimes falsely 4-celled); style thread-like; 

 stigma 2-lobed. Fruit a dehiscent 4-valved capsule or a more or less fleshy 

 berry, the surface spiny or smooth. Seeds numerous, compressed laterally, 

 discoid or imperfectly ear-shaped, sometimes with a cork-like covering; 

 embryo curved, cotyledons semiterete. — Herbs, shrubs, or small trees, glabrous, 

 farinaceous, or pubescent. Leaves broad, thin, entire, angulate, or coarsely 

 sinuate-dentate. Flowers solitary, erect or drooping, sometimes very large. 



KEY TO THE SECTIONS 



F'lowers erect; calyx circumscissile near the base, the base persistent and ex- 

 panding like a frill, shield or cup. 

 Fruit an erect dehiscent 4-valved capsule. I. Stranwnhim. 



Fruit inclined or nodding, not dehiscing regularly. 



Plants terrestrial; pericarp spiny or tuberculate, with an expanded, frilled 



or shield-like calyx-base. II. Dutra. 



Plants aquatic or marsh-loving; pericarp smooth, with small discoid or 

 cup-like calyx-base. III. Ceraiocaidis. 



Flowers pendulous; calyx not circumscissile, either falling off entirely or per- 

 sisting like a husk appressed to the fruit, the latter unarmed and inde- 

 hiscent, spheroid, lemon-shaped, fusiform, or elongated and terete. 



IV. Brugmansta. 

 vSection I. Stramonium Gaertner. 



Flowers erect; calyx tube circumscissile near the base, falling off together 

 with the corolla, the base persisting and expanding into a disc, the margin of 

 which is at length turned downward and frilled. Corolla distinctly 5-lobed, 

 the lobes separated by emarginate sinuses. Fruit (Fig. i. A) an erect regu- 

 larly dehiscent 4-valved capsule, armed with rigid spines or unarmed. 



Type of the section, Datura stramonium L. 



KEY TO THE SPECIES 

 Capsule normally armed with subequal spines, these sometimes much abrevi- 

 ated or wanting; flowers white or lavender-coloied. i. D. stramonium . 

 Capsules armed with strongly unequal spines, the upper ones longer and 

 stouter. 

 Leaves ovate or oblong; sinuate- toothed or angled. 2. D.ferox. 



Leaves pinnately lobed. 



Branches, petioles, and calyx downy or woolly. 3. D. quercifolia. 



Branches, petioles, and calyx villous or hair}% 4. D. villosa. 



1. Datura stramonium L. Sp. PI. 1: 179. 1753. 

 Datura tatula L. Sp. PI. ed 2. i: 256. 1762. 

 Datura inermis Jacq. Hort. Vindob. 3: 44. pi. 82. 1776. 

 Type Locality: "Habitat in America, nunc vulgaris per Europem." 

 Range: Throughout eastern North America, Central America, and South 

 America; introduced at a very early date into the warmer regions of Eu- 

 rope, Asia, and Africa. 



A common weed in waste places, used by the Algonquin Indians as a nar- 

 cotic* The purple -flowered variety is commonly known under the name 

 D. tatula, the form with unarmed fruits as D. inermis. 



* For the origin of its common name, Jamestown, or Jimson, weed, see BEVERLEY, Hist. 

 Virginia, book 2, p. 24. 1706. 



