176 THE STORY OF PLANT LIFE 



laster or thyrsus. They are irregular^ hermaphrodite, 

 or gynodioecious, with two bracts to each whorl, and 

 a pair below each inflorescence. They are hypo- 

 gynous, with the parts usually in fives. The calyx is 

 hypogynous, gamosepalous, with five sepals, or two- 

 or three-lobed, tubular, bell-shaped, funnel-shaped, 

 occasionally two-lipped, ribbed, inferior, persistent 

 in fruit. The corolla is gamopetalous, two-lipped, 

 the separate petals not well marked, but with a tube 

 and a four to five irregularly-lobed limb, making 

 two lips, the upper outermost. It is deciduous, 

 overlapping in bud. The stamens are four, didy- 

 namous, or equal, epipetalous, inserted on the tube, 

 with a fifth (rarely present), and two lateral, im- 

 perfect. There may be only two stamens. The 

 anthers are polymorphous, opening inwards. The 

 pistil is syncarpous, superior. The ovary is situated 

 on an annular honey-disc of two carpels. It is very 

 soon constricted. It is four-lobed, with one erect 

 ovule in each lobe, and a single central style, with a 

 simple or two-lobed stigma. The style is placed 

 between the two lobes of the two carpels united 

 below. The fruit consists of four nutlets or achenes, 

 one-seeded. Rarely it is a drupe. The seeds have 

 no endosperm, and are erect or nearly so. The 

 cotyledons are fleshy. The embryo is usually 

 straight. 



The flowers are usually proterandrous. Honey is 

 secreted at the base of the tube. The lower lip 

 serves as an alighting-place for insects, and the 



