Rutaceae. 
Xanthoxylum mauiense Mann. 
Ae or Heae. 
XANTHOXYLUM MAUIENSE Mann, Proe, Bost. Soe. Nat. Hist. X. (1866) 319, et Proe. 
Am. Acad. VII. (1867) 160, et Fl. Haw. Isl. Proce. Ess. Inst. V. (1867) 170;— 
Hbd. Fl. Haw. Isl. (1888) 74;—Del Cast. Ill. Fl. Ins. Mar. Pac, VI. (1890) 180.— 
Fagara mauiensis Engler in Engl. et Prantl Pfizfam, III. 4. (1895) 119. 
the blade; panicles 3.5 to 10 em long many flowered, the common peduncle 2.5 to 4.5 em, 
the pedicels about 4 mm, tomentose; follicles 8 to 10 mm, stipitate, lunulate-obovoid, the 
apex almost lateral, after dehiscence recurved, rugose and pitted. 
This species seems to be indeed a very variable one; the writer has collected 
material of this species on Maui, Hawaii and Lanai, and even specimens of a 
small tree were collected by him on Kauai, which seems to be intermediate be- 
tween Y. mauiense and Y. hawaiiense; the petiolules of the lateral leaflets being 
shorter than in hawaiiense, but longer than in mauiense. The specimens from 
the above-mentioned islands vary considerably, especially those from Lanai, and 
from Maui proper. Horace Mann’s type came from West Maui, in which 
latter locality the writer did not find any Xanthoxylum. The specimens on 
which Mann based his species were collected by Remy n. 615. and Lydgate, but no 
definite locality is given, other than West Maui. It is the writer’s opinion 
that the tree must be a dry district species, as all other varieties occur in the 
mixed forests, rather than in mesophytie forests. The writer’s specimen which 
comes closest to the original description came from the lava fields of Puuwaa- 
waa, North Kona, Hawaii, on the slopes of Mt. Hualalai (no. 3716), where the 
genus Xanthoxylum has numerous representatives. 
The leaves and inflorescence are quite pubescent, and the former opaque, and 
as a whole answer well to Mann’s description; there seems, however, to be a 
transition type present which has the pubescent leaves, and besides being tri- 
foliolate, has also five leaflets, which would remind one of Y. kauaiense. The 
Species is dioecious, a fact of which Hillebrand was not certain. 
Specimens gathered on the Island of Lanai, in Mahana Valley (no. 8112), un- 
doubtedly will have to be referred to this species, though differing from it in 
the less coriaceous and perfectly glabrous leaves, and may therefore be ealled 
forma glabrum f. nov. Hillebrand describes a var. B. from Maunahui, Molokai, 
which differs from the species in the very long petioles 5 to 10 em, the leaves of 
which are glabrous above and coarsely pubescent underneath, with pellucid dots 
along the margin. The writer is unacquainted with this variety. 
Another variety deseribed by Hillebrand as var. y the writer collected on Lanai. 
This latter tree is indeed quite common on Lanai, occurring on the main ridges 
Lanaihale and Haalelepakai; elevation 3000 feet. It may be described as follows: 
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