if 



191 1.] Identification and Eradication of Weeds. 749 



a finely fibrous root, and the hypocotyl is long, slender, 

 smooth, and pearly. The cotyledons (Fig. 1, b') are very 

 variable in shape, and may be round-oval, nearly oval, or 

 nearly lanceolate ; they are broader towards the base, light 

 green, smooth, and shortly petioled, the petiole being chan- 

 nelled above and tinged brownish. The blade of the cotyledon 

 is T V to i in. long by to } in. broad (2*5 to 6 mm. long 

 by 17 to 5 mm. broad). 



In the second stage seedling (Fig. 1, c) the cotyledons 

 have attained their maximum growth, and the petioles are 

 roughly as long as the blades of the cotyledons, The first 

 leaves are radical, petiolate, broadly ovate, with notched 

 margins, and have a well-marked mid-rib, with veins clearly 

 showing at the back. The stalks are long, rather broad, 

 channelled above, convex below, and slightly and minutely 

 hairy. 



The third stage seedling (Fig. 1, d) shows a central stem, 

 while incipient branches are appearing. The leaves are 

 larger and more clearly notched at the margins ; they are 

 light green above, and silvery beneath, with central mid-rib 

 or vein alternately branched. A few minute hairs occur on 

 the leaf stalks and margins. 



Mature Plant. — The plants grow quickly, and when they 

 reach the flowering stage (Fig. 1, e) are 6 to nearly 18 in. 

 high, and the stem is angular and branched, with a large 

 pinnatifid stipule on each side of the leaves. The flowers 

 (Fig. 1, e and e') spring from the axils of the leaves with 

 the stem, and are borne on long stalks; they are J to ij in, 

 in diameter, and, as the specific name tricolor implies, are 

 roughly three-tinted, the colours being very variable — whitish 

 purple, lilac, pale yellow or golden yellow, sometimes parti- 

 coloured. The flowering-period is from May to September, 

 and the plant is widely distributed in Europe, Northern 

 Africa, Asia, North-West India, and America. The fruit 

 is a three-valved capsule containing many of the hard, 

 slippery seeds. There are large numbers of cultivated 

 varieties of Viola tricolor, which are among the most beau- 

 tiful of our garden flowers. Anne Pratt states that "The 

 flower, when bruised, has a faint scent of peach kernels, an 

 odour which is more powerful in the cultivated kinds, and 



