1926 



A TEXTBOOK OF THEORETICAL BOTANY 



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earliest times. It was long held to be highly sacred and to possess magical 

 powers. 



Several species are of economic importance, particularly Tectona 

 grandis which is a large forest-tree occurring especially in Java and Burma. 

 It is the source of Teak, a hard and very durable wood used especially in 

 shipbuilding. The wood sinks in water unless thoroughly dried, which in 

 India is effected by removing a ring of bark and sapwood from the base of 

 the tree. The tree soon dies and thereafter is left standing for two years 

 before being cut, by which time it is completely dry. Another interesting 

 genus is Avicennia, with three species which are normal inhabitants of 

 mangrove swamps and extend into the subtropics. The stems of this 

 shrub increase in thickness by the repeated production of new cambia 

 outside the original one. Caryopteris mastacanthus (Fig. 1853) is grown in 

 gardens. It is a low-growing shrub with heads of violet flowers, blooming 

 in the autumn. 



Fig. 1853. — Caryopteris mastacanthus. Flower- 

 ing shoot with axillary inflorescences. 



The flowers of the Verbenaceae are generally pentamerous, though 

 reduction in the number of stamens is very common. Tectona is exceptional 

 in having five. The gynoecium usually comprises two carpels, but there 

 are four in Duranta, and five in Geiinsia. The loculi are frequently divided 

 into one-seeded portions by false septa which have been developed 

 secondarily. The fruit is generally a drupe, sometimes a capsule. The 

 family is distinguished from the Labiatae by the terminal and not gynobasic 

 style and the undivided ovary. 



