Hawaiian Hibiscus — Roe 
31 
elevation 1500 feet, edge of woods; tree 8 m. X 
25 cm., November 8, 1936, St. John 17,655* 
Mokuleia Trail, Waianae Range, elevation 2200 
feet, tree 6 m., January 11, 1948, Webster l L. 
radyJISUr- ^ 
X Grat 
~~T 
his population was brought to our attention 
in 1944 when Skottsberg published it as a form 
of H. Arnottianus Gray. Skottsberg felt that the 
variation was slight and showed principally in 
the smaller flower. Resides the flower difference, 
the leaves, calyx, and bracts of this form appear 
smaller than those of the species. 
15. Hibiscus Arnottianus Gray var. punaluuen- 
sis Skottsberg 
Fig. 23 
Hibiscus Arnottianus Gray var. punaluuensis 
Skottsberg. Vascular Plants from the Ha- 
waiian Islands, IV. Acta Hort. Gotoburg. 
15: 396. 1944. 
H. punaluuensis (Skottsb. ) Deg. & Deg. 
Flora Hawaiiensis 5: Family 221. 1957. 
DESCRIPTION: Tree to 35 ft. Stipules subulate, 
caducous. Petioles densely puberulent, 3-12 cm. 
long, scarcely palmately veined ( 5 radiating 
ribs), veins strongly pubescent. Blade 10-25 cm. 
long, 8-20 cm. wide with puberulent-pilose sur- 
face, ovate, base subcordate, apex acuminate. 
Bracts 5-7, linear-lanceolate, 1. 0-2.0 cm. long, 
pilose. Calyx scabrous, 1.8-2. 5 cm. long, 1.0—1. 5 
cm. wide, cleft 5 mm. Petals white, 8-12 cm. 
long, 2.5-4 cm. wide, stellate pubescent on outer 
surface. Staminal column red, 12—19 cm. long, 
free filament tips 1.5-2. 5 cm. long, red. Style 
branches 1.0 cm. long. 
HOLOTYPE: Punaluu, Koolau Mountains, 
Oahu (Hawaiian Bog Survey) Sept. 27, 1938. 
0. Selling 3638. (Isotype examined; type not 
seen. ) 
SPECIMENS EXAMINED: Oahu: Edge of Ka- 
luanui Stream, Castle Trail, December 22, 1940, 
E. H. Bryan, Jr. 1501. Between Punaluu and 
Kaipapau, Koolau Mountains, November 14-21, 
1908, C. N. Forbes. Near Head Gate, Wahiawa, 
August 17-20, 1915, C. N. Forbes 2198.0. Puna- 
luu, elevation 2000 feet, September 28, 1930, 
E. Y. H osaka 304. Kaluanui River Bank, Koo- 
lau Mountains, elevation 2800 feet, September 
28, 1930, Inafuku. Upper Kaluanui Valley, Castle 
Trail, October 21, 1945, R. Kuykendall 117. 
Waiahole Ditch Trail, June 1932, A. Mee- 
hold. Near Mt. Stream, Koolau Mts., Nov. 
14-21, 1908, Rock 37 (309) (duplicate). In 
cultivation in Wilder’s Garden, J. F. Rock. Along 
Puunahia streams near Castle Camp, tree 30 feet, 
August 1911, Rock 8831. Kaluani, Castle Trail, 
Koolau Range, November 14, 1955, Roe 18. 
Kaluanui, by stream 1950 feet altitude, rain 
forest, tree 7 m. X 15 cm., November 25, 1956, 
St. John 25977. 
Skottsberg in 1944 established this new vari- 
ety, punaluuensis, and called it after the locality 
where the type was collected. It differs from the 
species by a characteristic venation: between 
the base with the five radiating ribs and the 
next strong pair (which forms an angle of 45 
degrees with the midrib) is a wide stretch with 
only faint veins issuing at an angle of about 90 
degrees. The leaves are longer and wider than 
those of the species, the petiole being approxi- 
mately 5 cm. longer. The veins are strongly 
pubescent. The free filament tips and style 
branches are longer in the variety. The calyx 
is conspicuously hairy. 
In 1957 Otto Degener raised this population 
to the status of a species. These plants differ 
from H. Arnottianus but show such similarity 
that I hesitate to agree with Degener. The dif- 
ferences are not so great as they are between 
the other taxa which have been accorded specific 
rank. Skottsberg’s treatment seems more satis- 
factory. 
REFERENCES 
Gaum, Edward L. 1930. New Hawaiian plants. 
Bishop Mus. Occ. Pap. 9(5). 
Degener, Otto. 1957. Flora Hawaiiensis, Book 
V. Honolulu. 
Forbes, Charles N. 1912. New Hawaiian 
plants, III. Bishop Mus. Occ. Pap. 5(1). 
Gaudichaud, Charles. 1826. Botanique du 
Voyage de 1’Uranie. Paris. 
Gray, Asa. 1854. Botany Phanerogomia, Vol. 
I. U. S. Expl. Exped. During the Years 1838. 
...George P. Putnam & Co., New York. 
Heller, A. A. 1897. Observations of the ferns 
and flowering plants of the Hawaiian Islands. 
Minn. Pub. Bot. 
