KEY TO THE SPECIES 49 



1. MALVA (Mallow) 



Low herbs with a 3-leaved involucre at base of calyx like an outer caljrx, 

 inversely heart-shaped petals, and numerous ovaries united into a ring around a 

 central axis and forming a flattened fruit which separates at maturity into as 

 many kidney-shaped blunt carpels. 



1. Malva rotundlfolia L. (Common Mallow). Stems procumbent ; leaves 

 round heart-shaped on very long petioles, crenate, obscurely lobed ; petals whitish, 

 twice the length of the calyx ; carpels hairy. Boadsides and cultivated grounds. 



2. MALVASTRUM (False Mallow) 



Herbaceous, somewhat tufted perennials with racemose flowers and 10-15 

 rugose-reticulated carpels. 



1. Malvaetrum coccineum (PurshJ Gray (Red False Mallow). Low and 

 branched, 1-2 dm. high ; cinerous, with stellate-pubescence ; leaves pedately 

 lobed, the segments toothed or incised ; flowers in dense terminal racemes, con- 

 spicuous, 15^80 mm. broad ; carpels rugose. Common on the plains everywhere. 



XL. VIOLACEiE (Violet) 



Herbs with leaves all basal or alternate and with, stipules, 

 axillary nodding ilowers, 5 sepals, an irregular 1-spurred corolla 

 of 5 petals, 5 stamens conniving over the pistil, a single style, 

 and a 1-celled ovary becoming a pod which splits into 3 divi- 

 sions. 



1. VIOLA (Violet) 



Herbs with sepals extended into ears at base, the lower petal spurred at base, 

 the 2 lower stamens bearing spurs which project into the spur of the corolla, and 

 a club-shaped style. (See Plant Relations, p. 117, Fig. 131 ; also Plant Structurea 

 p. 229, Fig. 811.) 



* Flowers yellow, more or less purple veined, sub-acaulescent. 



1. Viola Nuttallil Pursh (Ndttall's Violet). Nearly stemless and glabrous; 

 leaves spreading, lanceolate, obscurely repand or crenate, 4-8 cm. long, tapering 

 into a petiole as long as the blade ; peduncles shorter than the leaves ; sepals 

 lance-acuminate, the yellow corolla rather small. Frequent on the open sandy 

 plains. 



2. Viola valllcola Aven Nelson (Violet of the Valley). Similar, but stem 

 evident, glabrous or puberulent ; roots faseiled, fibrous-fleshy ; leaves entire, from 

 broadly to narrowly ovate, with rounded or even sub-cordate base, obtuse apex, 

 the petiole equalling or longer than the blade ; the yellow flowers larger. Moist 

 fertile mountain valleys. 



* * Flowers not yellow, leafy stemmed or stemless. 



3. Viola Canadensis L. (Canada Violet). Upright, 1-3 dm. high ; leaves 

 heart-shaped, pointed, serrate ; stipules entire ; flowers white or whitish inside, 

 the upper petals mostly tinged with purple beneath, the lateral ones bearded. 

 Rich woods. 



