8. Viola papilionacea Pursh. Meadow violet, common blue violet. 



Plant glabrous; rhizome horizontal, stout, branching; petioles usually smooth and 

 glabrous, sometimes sparingly pubescent; leaf blades reniform to ovate in outline 

 above the cordate base, becoming as much as 13 cm. wide, acute or abruptly 

 pointed at apex, crenate with the teeth 2-7 mm. long and 0.5-2 mm. wide; flowers 

 shorter than or sometimes overtopping the leaves, usually rich-violet and white- 

 centered; corolla 2-3 cm. across, the spurred petal cymbiform; cleistogamous 

 flowers on horizontal peduncles, their capsules (1-1.5 cm. long) ellipsoid to 

 cylindric and usually purplish; seeds dark-brown. 



In low alluvial soil bordering streams, ponds, wet ditches, fields and meadows, 

 thickets and low wet woods, in Okla. (Waterfall), Mar .-May; Me. and Que. to 

 N.D. and Wyo., s. to Ga. and Okla. 



9. Viola Langloisii Greene. 



Acaulescent perennial, reproducing vegetatively by fragmentation of the hori- 

 zontal rhizome; leaves small, short, spreading, ovate, with cordate bases and slightly 

 attenuate apices, with 10 to 14 teeth in upper third of each margin, completely 

 glabrous; flowers blue-violet, borne on erect peduncles above the leaves; sepals 

 narrow, slightly sagittate. 



River forests, wet or damp slopes and edge of streams, in Okla. ( Waterfall) and 

 e. Tex., especially in the s.e., Mar.-Apr.; cen. Tex., and Okla., e. to cen. Fla., n. to 

 n. Miss. 



10. Viola missouriensis Greene 



Acaulescent perennial, reproducing vegetatively by fragmentation of the thick 

 horizontal rhizome; leaves large and numerous, often 20 to 30 produced from one 

 crown, ovate to orbicular, with cordate bases, triangular at apex, with to 6 

 widely spaced crenations, glabrous; flowers light-blue, borne on erect peduncles 

 about same length as petioles; sepals broad, the auricles not pronounced; grading 

 into V. Langloisii. 



In low rich alluvial woods, bogs, river forests, along streams and ledges, in 

 Okla. (Waterfall), cen. and n.e. Tex. and N.M. (San Miguel Co., fide Wooton & 

 Standley), Mar.-May; s. Tex. e. to Ark., n. to Minn, and Neb., w. to N.M. 



Fam. 93. Lythraceae St.-Hil. Loosestrife Family 



Herbs, shrubs or trees; leaves opposite, whorled or alternate, simple, entire; 

 stipules minute or wanting; flowers perfect, regular or sometimes irregular, solitary 

 or clustered. 4- to 7-parted, the peduncles usually bibracteolate; calyx tubular to 

 campanulate, persistent, 4- to 6-toothed and often with accessary teeth in the 

 sinuses, the toothlike lobes valvate; petals inserted in the throat of the hypanthium 

 between the lobes or rarely absent; stamens 4 to many, inserted on the hypanthium, 

 when as many as the petals then opposite the sepals; style simple or wanting, the 

 stigma capitate; fruit capsular, dry, 1- to several-celled. 



About 550 species in 25 genera, mostly in the tropics. 



Ducks are known to eat the seeds of some species, notably those of Decodon and 

 Lythrum, and it is quite possible that other wildfowl eat seeds of these plants. 

 Small mammals also eat the seeds as well as parts of the herbage of most species. 



1. Erect or viny shrubs (2) 



1. Herbs or only partially suffrutescent (3) 



2(1). Flowers in cymes in leaf axils; aquatic shrub 1. Decodon 



2. Flower solitary in leaf axils; not strictly aquatic 2. Heimia 



1154 



