Casuarinaceae. 61 
Subclass Dicotyledon es. 
Plants belonging to this subclass have a more complex stem- 
structure, the fibrovascular system being arranged in concentric 
layers; these are divided into medularry rays which radiate from a 
central column called the pith. By tar the greatest number of 
plants belong to this subclass. 
CASUARINACEAE 
Casuarina equisitifolia Stickman. 
I RON' WOOD. 
Plate XXVI I. 
The Ironwood is a large, rapid-growing, evergreen tree, with 
leafless branches which are drooping, cylindrical, and have sheaths 
of awl-shaped scales at the joints. They are deciduous and take the 
place and perform the functions of leaves. It has the appearance of 
a pine. The branches are jointed like an equisitum stem, hence the 
name. 
The genus Casuarina, named on account of the pendant branch- 
lets, resembling the feathers of the Cassowary, was formerly classed 
with the conifers, but is now recognized as the only known genus 
of a distinct family. 
The tree, which is planted as wind-breaks and is especially com- 
mon near the seashore at Waikiki and Kapiolani Park, attains a 
very large size and diameter of trunk ; it loves the sandy tracts near 
the sea and forms on some of the South Pacific Islands the greater 
portion of the strand forests of which the Hawaiian Islands are so 
devoid. The tree is of very wide distribution, ranging from Aus- 
tralia to the Malayan Islands, India and the islands of the Pacific. 
It is now cultivated in many tropical or subtropical countries and 
can be found in Florida, California, and parts of South America. 
Nice avenues of this tree, one of which is here figured, can be found 
in Kapiolani Park at Waikiki, while single trees can often be seen 
on residential premises. 
The bark of the Ironwood is used in tanning, and a brown dye 
is extracted from it. It is slightly astringent and is used as a tonic 
in infusions, as well as being useful in treating chronic dysentery. 
The wood is exceedingly hard ; it cracks and splits, however, and 
is difficult to cut. As firewood it serves well, as it burns readily and 
the ashes retain the heat for a long time. In Fiji the natives use the 
