152 FOUNDATIONS OF BOTANY 



2 oval glands near its summit. Flowers 2-3 in. wide, solitary ; 

 peduncles 3-bracted, longer than the petioles ; calyx-lobes with a 

 small horn-like appendage on the back near the apex, white within. 

 Petals and crown purple and white. Fruit yellow, about the size 

 and shape of a hen's egg, edible. Seeds with a pulpy aril. Com- 

 mon along fence-rows and embankments S.* 



2. P. lutea, L. Yellow Passion-flower. Perennial. Stem 

 slender, smooth, 6-10 ft. long. Leaves broadly heart-shaped, 3-lobed 

 at the summit, entire, often mucronate ; stipules small ; petioles 

 without glands. Peduncles longer than the leaves, usually in pairs. 

 Flowers greenish-yellow, ^-f in. wide. Fruit purple, oval, ^ in. 

 long. Woods and thickets S.* 



68. BEGONIACEiE. Begonia Family. 



Chiefly perennial herbs or low shrubs, with fleshy or very 

 juicy stems. Leaves alternate, generally heart-shaped at the 

 base, often very un symmetrical; stipules deciduous. Flowers 

 monoecious, in cymes or other clusters, on axillary peduncles. 

 Stamens many (Fig. 18). Pistillate flowers with the floral 

 envelopes borne on the ovary ; ovary 3-angled or 3-winged 

 (Fig. 18), very many-seeded. 



BEGONIA, L. 



Flowers with the calyx and corolla of the same color, 

 staminate and pistillate ones both occurring in the same clus- 

 ter. Sepals usually 2. Petals 2 or in the fertile flowers 3 or 

 4, sometimes wanting. Stamens many in a cluster, with short 

 filaments. Styles of the fertile flowers 3, often with long, 

 twisted stigmas (Fig. 18, C). The genus contains a great num- 

 ber of species and varieties, cultivated from tropical or sub- 

 tropical regions, of which only a few of the commonest are 

 here described. 



1. B. Rex, Putz. Herb, stemless or nearly so, from a fleshy root- 

 stock. Leaves large, taper-pointed, very unequally heart-shaped, the 

 margin sinuous, often bristly fringed, upper surface wholly silvery or 

 mottled silvery and dark green, lower surface green or reddish or of 

 both colors. Flowers few, large (1^ to If in. in diameter), varying 

 from yellow to pinkish. Cultivated from the Himalayas ; many 

 varieties. 



