FLOWERING PLANTS AND FERNS OF ARIZONA 621 



8. Anthers innate, attached near the base, erect; petals white or pink 

 (9). 

 9. Petals distinctly clawed, the claw at least one-fourth as long as 



the blade '__ 5. Clarkia. 



9. Petals not or scarcely clawed, the claw not more than one-tenth 

 as long as the blade 6. Godetia. 



1. JUSSIAEA 



Plants -perennial, herbaceous, aquatic; leaves alternate; flowers 

 5-merous, solitary in the leaf axils; ovary 5-celled, many-ovuled ; 

 capsule cylindric-clavate. 



1. Jussiaea repens L., Sp. PL 388. 1753. 



Known in Arizona from a single collection in shallow water, Papago 

 Park near Tempe, Maricopa County (McLellan and Stitt 671), May 

 to October. 



Yellow-waterweed. The species is represented in Arizona by var. 

 peploides (H. B. K.) Griseb. (J. calif arnica (S. Wats.) Jepson), 

 which ranges from Oregon to South America. 



2. LUDWIGIA. Seedbox 



Plants perennial, herbaceous, inhabiting marshes and w r et places; 

 leaves opposite (in the Arizona species); flowers 4-merous; petals 

 often lacking; stamens 4; ovary flattened at the broad apex; capsule 

 short, 4-valved. 



1. Ludwigia palustris (L.) Ell., Bot. S. C. and Ga. 1: 211. 1821. 



Isnardia palustris L., Sp. PI. 120. 1753 



Banks of "El Kiatu" (probably Rillito Creek), south side of the 

 Santa Catalina Mountains (J. G. Lemmon 176), reported also by 

 Shreve from the same mountains. Nova Scotia to California, south- 

 ern Arizona, and Guatemala. 



Marsh purslane. Characterized by longitudinal green bands on 

 the fruit and by the 4 persistent sepals. The form that occurs in 

 Arizona is var. americana (DC.) Fern, and Griscom. 



3. ZAUSCHNERIA. Hummingbird-trumpet 



Plants perennial, herbaceous, somewhat woody at base and with 

 shredding bark; leaves sessile or nearly so, more or less fascicled, elliptic 

 to elliptic-lanceolate, somewhat coriaceous, usually denticulate, pallid, 

 more or less villous; flowers mostly 3 to 4 cm. long, scarlet, horizontal, 

 fuchsialike. 



1. Zauschneria latifolia (Hook.) Greene, Pittonia 1: 25. 1887. 



Zauschneria calif ornica Presl var. latifolia Hook., Curtis's Bot. 

 Mag. 76: pi. 4493. 1850. 



Greenlee and Gila Counties southward to the Mexican border, 

 westward to the Ajo Mountains (Pima County), dam]) places on rocky 

 slopes and in canyons, 3,500 to 7,000 feet, August to December. 



The Arizona form is var. arizonica (Davidson) Hilend (Z. arizonica 

 Davidson), the type of which was collected at Met calf, Greenlee 

 County (Davidson 365), and which occurs in southwestern New Mex- 

 ico, southern Arizona, and northern Sonora. 



