IN CEYLON. 45 



feet 6 inches) at 135 years, and 1,828 mm. (6 feet) at the 

 age of 200 years. 



The following observations were made on trees growing in 

 the Peradeniya Garden : 



Circumference of Trees in Millimetres. 



Species. 



Date of D. Embryopteris. D. Gardner!. D. Ebenum. D. quaesita. 

 Observation. mm. mm. mm. mm. 



The selected trees were of unknown age, and, as is shown in 

 the first measurements, of widely different dimensions ; it 

 is, nevertheless, of interest to know that in trees of the 

 selected species the increase in circumference may be from 

 29 to 102 mm. in three years' time. This increase may be due 

 to phellogenetic activity as much as that of the vascular 

 cambium, but assuming that the increase in circumference is 

 due to the production of secondary xylem only, we find that 

 that in D. Ebenum is equal only to 62 vessels, or an average 

 of one to two vessels along each radius, per month during 

 the three years in question. 



Timber. 



The genus Diospyros has obtained its widespread recog- 

 nition mainly in virtue of the valuable timber yielded by 

 several of its species. The term ebony is loosely applied to 

 any black heavy wood capable of taking a good polish, and 

 from time to time there has been considerable discussion as 

 to the exact botanical source of the ebony of the ancients. 

 Many plants are known to yield timber which in colour and 

 density resembles the real ebony, and botanists have been 

 found who assert that the ebony of the ancients was not 



