8 
PACIFIC SCIENCE, Vol. XV, January 1961 
TABLE 1 
PART 
H. Y oungianus 
H. furcellatus 
Stipules 
length 5-6 mm. 
length 8-10 mm. 
vesture hirsute 
vesture short, stellate 
Leaf color 
"Scheele green” (yellowish green) 
"grass green” (bluish green) 
Leaf shape 
apex acute 
acuminate 
blade roundly lobed 
blade acutely cleft 
Stem 
puberulent, hirsute 
pilose 
Bracts 
length 1—1.3 cm. 
length 1. 5-2.1 cm. 
vesture densely hispid 
vesture short, stellate 
hairs 1-1.5 mm. in length 
hairs microscopic 
Calyx of fresh flower 
sepal length 2.2-2. 5 cm. 
sepal length 1.7-1. 8 
calyx diameter at throat 1.5-1. 8 cm. 
calyx diameter at throat 1.1-1. 3 cm. 
densely hispid 
sparsely hispid 
cleft 1 cm. from sepal apex 
cleft 1.8 cm. from sepal apex 
veins raised 
veins extremely raised 
Petals 
length 5. 8-6. 5 cm. 
length 4-5 cm. 
width 4-4.5 cm. 
width 2.5-3 cm. 
color, "mallow purple” (deep pink) 
color, light "phlox purple” (pale pink) 
Hillebrand is correct in stating that H. Y oung- 
ianus is a marshland plant, for I have collected 
it growing in several inches of water in the cen- 
tral area of Kawainui Swamp, Oahu, and sim- 
ilarly in water at the foot of Wailua Falls, Kauai. 
But likewise, Mrs. Sinclair could be correct in 
her statement of locality, for I have recently 
observed it in upper Manoa on a rather dry 
slope, but in a rainy belt. The species, however, 
grows more luxuriantly and flowers continually 
in a wet environment. I have grown it in areas 
FIG. 2. Hibiscus Y oungianus Gaud, ex H. & A. 
of little rainfall. It continues to grow, but much 
less vigorously than in swamp areas. 
Heller (1897) is incorrect in stating, "It is 
found only on Oahu.” It has been collected on 
all of the major islands except Molokai, Lanai, 
and Niihau. (See Fig. 3.) 
SPECIMENS EXAMINED: Hawaii: Rainbow 
Falls, May 16, 1915, C. N. Forbes 525. H. Lava 
flow near Hilo, May 17, 1915, C. N. Forbes 
545.H. 
Kauai: Hanalei, August 4, 1909, C. N. Forbes 
128.K. Wailua Falls, October 5, 1916, C. N. 
Forbes 498.K. Wailua Falls, July 26, 1957, on 
the bank of the pool at the bottom of the falls, 
Roe 251. Weoweopilau Stream, on banks of 
stream near cane fields, altitude 500 feet, July 
28, 1957, Roe 256 . 
Maui: Haleakala, October 10, 1922, Skotts- 
berg 793. 
Oahu: Woodlawn, Manoa, October 2, 1933, 
Neal. Waihole Valley, November 4, 1938, Neal. 
Waihole Ditch, May 1957, Pearsall. Kawainui 
Swamp, Kailua, May 4, 1930, St. John. Manoa 
about 500 yards off Woodlawn Drive, about 
mile west of Old Ti Slide, altitude 550 ft., Octo- 
ber 31, 1956, Roe 203. Kawainui Swamp, Kai- 
lua; plant growing in water, December 31, 1956, 
Roe 205. 
Hawaiian Islands: H. Mann & W . T. Brig- 
ham 598. Onekahakale Beach, August 15, 1936. 
V. O. Fosberg 64. 
