CELLS. SCLEROGEN. 
63 
of the Ivory-nut , and shell of the Coquilla-nut , being 
turned into handles for walking-sticks, umbrellas, and 
other articles as a substitute for true ivory. The Coquilla 
is a species of Cocoa-nut , and full two centuries ago 
received the name of Cocos lapidea from its stony hard- 
ness. The Ivory-nut , when first imported into this 
country is so soft as to he readily cut with a knife, and 
is of a milk-white colour, but it soon hardens, and 
although so very dense, yet, when cut sufficiently thin, 
still exhibits its cellular character. It is composed of 
long oval cells, having large elongated central cavities, 
from which, numerous canals radiate towards the margin 
of the cell, at this point, as 
shown in Fig. 46, they are 
considerably dilated. It is 
curious to observe that the 
pores or canals in adjoin- 
ing cells almost invariably 
correspond at their circum- 
ferential extremities, and yet 
otherwise communicate, the 
intervening cell wall being 
always present, as seen in 
Figs. 46 and 47- In a 
transverse section of the 
same nut, Fig. 47, the size 
of the central cavity, and the 
pores coming off from it as 
they in no case meet or 
FIG. 46 . 
Vertical section of the Ivory-nut 
