FLOWERING PLANTS AND FERNS OF ARIZONA 619 



national boundary, at ''margins of pools and mountain streams" 

 ( Wright 1063). Apparently known only from Sonora. 



R. ramosior (L.) Koehne is also to be looked for in Arizona. It differs from R. 

 dentifera in having the bractlets seldom surpassing the calyx, the appendages of 

 the calyx one-half as long as to slightly longer than the lobes, and the ovary 

 globose-ovoid. 



2. AMMANNIA 



Annual herbs, differing from Rotala chiefly by the characters given 

 in the key to genera, and in the plants being usually larger, with the 

 flowers in few-flowered axillary cymes. 



Key to the species 



1. Capsules equaling or somewhat surpassing the calyx lobes; flowers distinctly 

 pedicelled, the pedicels often elongate ■ 1. A. auriculata. 



1. Capsules not equaling the calyx lobes; flowers sessile or subsessile, the pedicels 



rarely up to 4 mm. long 2. A. coccixea. 



*1. Ammannia auriculata Willd., Hort. Berol. 1: 7. 1806. 

 Aiiimannia wrigktii A. Gray, PI. Wright. 2: 55. 1853. 



Not known definitely to occur in Arizona but was collected near 

 Santa Cruz, Sonora, and along the San Pedro River (in Arizona?) 

 [Wright 1062, type collection of A. wrightii), growing with Rotala 

 dent ijt ra. Missouri to Texas, Arizona (?), and southward. 



According to Koehne 90 all American specimens of A. auriculata 

 belong to var. arenaria (H. B. K.) Koehne. 



2. Ammannia coccinea Rottb., PI. Hort. Havn. Descr. 7. 1773. 

 Maricopa, Cochise, Pima, and Yuma Counties, 4,000 feet or lower, 



infrequent in wet soil or shallow water, late summer and autumn. 

 New Jersey to Washington, south to Florida, Arizona, and California; 

 South America. 



3. LYTHRUM. Loosestrife 



Plant herbaceous or nearly so, perennial, stoloniferous; stems erect, 

 very leafy, with exfoliating bark; leaves alternate or nearly opposite, 

 sessile, the blades of the stem leaves linear-lanceolate, those of the 

 basal shoots oblong or somewhat oblanceolate; flowers mostly solitary 

 in the axils, short-pediceled, forming slender leafy spikes, the petals 

 normally rose purple. 



1. Lythrum californicum Torr. and Gray, Fl. North Amer. 1: 482. 

 1840. 



Lythrum alatum Pursh var. linearifolium A. Gray, Boston Jour. 



Nat. Hist. 6: 188. 1850. 

 Lythrum linearifolium Small, Fl. Southeast. U. S. 828. 1903. 



Gila and Yavapai Counties to Cochise, Santa Cruz, and Pima 

 Counties, 1,300 to 5,500 feet, frequent in wet soil along streams and in 

 bogs, June to August. Texas to southern Nevada, Arizona, Cali- 

 fornia, and Mexico. 



1. CUPHEA 



Plant annual; stems erect, leafy, usually branched; leaves slender- 

 petioled. the blades broadly lanceolate to ovate, thin; flowers axillary, 



w Koehne, E. lythkaceae. Pflanzenreich IV. 2 - p. 46.) 



