Rutaceae. 
ridges, as on Konahuanui, Niu Valley, and in the Koolau range, where the tree 
is not uncommon. 
The bark, as of nearly all the other Hawaiian species of this genus, is thin 
and smoothish, with yellowish lenticels; in other species the bark is dark brown 
to black and has the appearance of having been burned; the granular mass will 
come off even when only touched, in others again the bark is covered with very 
narrow only slightly protruding confluent ridges. The wood of this, as of the 
other species, is yellow and bitter to the taste. 
Xanthoxylum hawaiiense Hbd. 
A’e or Hea’e. 
(Plate 77.) 
XANTHOXYLUM HAWAIIENSE Hbd. Fl. Haw. Isl, (188) 76;— Del Cast. Ill. Fl. Ins 
Mar. Pacif. VI. (1890) 129.—Fagara hawaiiensis Engler in Engl. et Prantl 
Pfizfam. ITI. 4. (1895) 119. 
A medium sized tree, glabrous; leaves pedately 3-foliolate, on petioles of 3.5 to 4.5 
em, the leaflets on petiolules of equal length, not articulate, but occasionally thickened- 
near the blade, acuminate, ovate to deltoid, the lateral ones unsymmetrical or subcordate, 
5 t 5 to 5.5 em wide; panicles in the axils of the leaves or at the end of 
the branches; follicles curved, almost smooth, but pitted, 1 em in diameter 
Hillebrand records this tree from the central plateau on the Island of Hawaii 
at 5000 to 6000 feet elevation, evidently from between Mauna Kea, Mauna Loa 
and Mt. Hualalai. The writer did not meet with this tree on that great plain, 
but collected specimens of an evident variety of this species on the slopes of 
Mauna Kea near Keaumoku, among composites such as Raillardia and Lipo- 
chaeta, near the extinct crater of Nohonaohae at an elevation of perhaps 4000 
On his last visit to North Kona, Puuwaawaa, he collected flowering specimens 
of a Xanthoxylum; in fact, the same species as found at Nohonaohae, referrable 
to XY. hawaiiense. The specimens were collected on the lava fields beyond Puu- 
anahulu joining the pahoehoe lava flow of 1859. The leaves of this tree as well 
as those from Nohonaohae are exceedingly strong lemon scented, exactly as those 
of Eucalyptus citriodora, which fact caused the manager of the Parker Ranch, 
on which land the trees are found, to believe that the tree was the lemon-scented 
gum. 
It is peculiar that Hillebrand should not have noticed such a strong aromatic 
odor, which none of our other Xanthoxyla possess; he, however, fails to mention 
anything about it. The true species, answering Hillebrand’s description in 
nearly every detail, was found by the writer on the southern slopes of Mt. Hale- 
akala, Maui, where the tree is, however, not abundant. There the trees have not 
the slightest odor of lemon, but the ordinary, somewhat soapy smell, as have the 
rest of our Xanthoxyla. In the latter locality the trees were in fruit during 
November, 1910, where the writer collected his first material of this species (no. 
8657 in the College of Hawaii Herbarium). 
195 
