72 SPRING FLORA 



called a pollinium. The two contiguous pollinia of 

 adjacent anthers are united. The pistil-system consists 

 of 2 separate ovaries, each with its style; and these 

 are surmounted by a single flat, 5-angled stigmatic 

 disk, which also surmounts the stamen-column. Fruit 

 a pair of follicles. Seeds tufted. 



Leaves opposite: corolla reflexed 1. Aselcpias 



Leaves alternate; corolla not reflexed 2. Asclepiodorn 



1. ASCLEPIAS. Milkweed. 



Erect or decumbent herbs from deep perennial roots. Leaves 

 opposite or whorled (rarely alternate). Inflorescence terminal 

 or axillary. Corolla deeply 5-parted, the segments reflexed. 

 Corona-hoods each with an incurved horn within. 



1. A. speclosa Torr. Stout, 1-2 */& ft. high, white-tomentose 

 or canescent all over. Leaves opposite; thick; broadly ovate 

 or elliptical; obtuse and cuspidate or acute. Umbels several 

 or rarely solitary. Corolla purplish. Column very short or 

 none. Follicles erect or spreading on the recurved pedicels, 

 woolly and spinose. In moist soil near springs and irrigation 

 ditches. June-July. 



2. ASCL.EPIODORA. 



Erect or decumbent stout herbs. Leaves mostly alternate 

 (sometimes opposite). Inflorescence terminal. Flowers large. 

 Corolla rotate, its segments spreading. Corona-hoods promi- 

 nently crested within. 



1. A. decumbens Gray. Stems decumbent or ascending: 

 rough-puberulent; 1-2 ft. long. Leaves somewhat leathery, 

 narrowly to broadly lanceolate; acuminate. Umbel solitary, 

 many-flowered. Flowers greenish with purple hoods. Fruiting 

 pedicels twice bent. Follicles ascending. Dry soil on hillsides. 

 June-July. 



ORDER POLEMONIALES. 



CONVOLVULACEJE. Morning-glory Family. 



Mostly trailing or twining herbs (erect in Oressa). 

 Leaves exstipulate, alternate (or scales in Cuscuta). 

 Inflorescence axillary, cymose or solitary. Flowers 

 regular, perfect. Calyx of 5 distinct, imbricated sepals. 

 Corolla of 5 united petals. Stamens 5, inserted on the 

 corolla, and alternate with its lobes. Pistils 2, or 1, 

 with 1-3 styles, and a "superior," 2-3- or falsely 4-6- 

 celled ovary. Fruit a 2-4-valved capsule, or 2-4 

 separate fruits. 



