WRIGHT : THE GENUS DIOSPYROS 



with unlike elements. When one end tapers the appearance 

 is very similar to that of a short fibre. 



. There is a little variation in the transverse, but consider- 

 able in vertical dimensions throughout the species. In some 

 species the relatively large transverse dimensions aid 

 materially in distinguishing them in the wood of young 

 twigs. 



The following are the dimensions of these elements 

 in the sapwood of the respective species : 



Radial Diameter. Length. 



D. Ebenum 

 D. quaesita 

 D. oocarpa 

 D. affinis 

 D. montana 

 D. Embryopteris 

 D. Moonii 

 D. attenuata 

 D. pruriens 

 D. acuta 

 D. hirsuta 

 D. Thwaitesii 

 D. crumenata 

 D. sylvatica 

 D. Gardner! 

 D. oppositifolia 

 D. Melanoxylon 

 D. ovalifolia 

 D. Toposia 

 D. insignis 



The thickness of the wall varies from O001 to 0*0016 mm. 

 These are the average radial dimensions and variations 



length of the wood parenchyma cells in the sapwood of 

 the several species. The age of the trees and the climates 

 under which they have grown are widely different, though 

 the above does not show any remarkable variation. 



Wood Fibres. These compose the greater part of the 

 secondary xylem, and are responsible to a great extent for the 

 durability of the timber. The occurrence in large numbers 

 of these elements of great length, with thick walls and 

 narrow lumina, enhances the value of any timber. 



