6 
PACIFIC SCIENCE, Vol. XV, January 1961 
l. Hibiscus Y oungiawus Gaud, ex H. & A. 
Figs. 1-3 
Hibiscus Y oungianus Gaud, ex H. & A. Bot. 
Beechey Voy., p. 79. 1832. 
H. furcellatus Lam. var. Y oungianus (Gaud.) 
Flochr., Ann. Conserv. Jard. Geneve, p. 132. 
1900. 
DESCRIPTION. Stiffly erect with a paucity of 
pithy branches, to 3 m. high (average ca. 2.5 
m. ) , diameter at base ca. 8 cm., hirsute and 
pilose throughout, lateral branches very strongly 
ascending, nearly parallel to the main stem. 
Leaves more abundant above, "Scheele green” 
in color (cf. Ridgway); stipules 5-6 mm. long, 
0.5 mm. wide, pubescent; petioles 9—1 3 cm. long, 
scabrous; blade 10-12 cm. long, 11-12 cm. wide, 
wide ovate, varying from nearly entire to mod- 
erately lobed, base cordate, upper portions acut- 
ish, margins serrate-dentate, both surfaces scab- 
rous-hispid, this more abundant on the veins; 
veins 5-9, palmately arranged throughout the 
blade. Peduncle axillary, 1.5 cm. long, 3 mm. in 
diameter, puberulent. Involucral bracts 10-12, 
1-1.3 cm. long, ca. 1 mm. diam., terete, bifid at 
apex. Calyx "Scheele green” (cf. Ridgway), 2.2- 
2.5 cm. long, 1.5-1. 8 cm. diameter at throat, 
hirsute, cleft 1 cm., lobes lanceolate, veins 10, 
prominent, gland on midvein of each lobe at 
the throat level. Petals "mallow purple” (cf. 
Ridgway), 5.8— 6.5 cm. long, 4-4.5 cm. wide, 
tubular at base, prominently nerved, microscopic 
hairs on both surfaces. Staminal column dark 
maroon-purple, 2. 0-3.0 cm. long; free filament 
tips extend 1-2 mm. from column, arranged in 
rings approximately 5 mm. apart; anthers deep 
purple; style inconspicuously exerted; style 
branches 1—2 mm. long, each terminating in a 
1 mm. discoid stigma. Ovary ca. 1.0 cm. long, 
8 mm. in diameter; seeds numerous, 2.8 mm. 
long, 2.0 mm. wide, dark brown, glabrous. 
This species was first brought to our atten- 
tion by Gaudichaud (1826): ". . . un hibiscus 
nouveau de la section 5 (furcaria) de M. De- 
candolle ( h. youngiana ) ...” ( nomen nudum ) . 
The first description was made in 1832 by 
Hooker and Arnott, who credited the species 
to Gaudichaud, ex Hooker and Arnott. Hille- 
brand (1888) included this species, as did Hel- 
ler (1897). Both authors regarded it as a true 
indigenous species. However, in 1900, Hoch- 
reutiner monographed the genus and reduced 
H. Y oungianus to a variety of H. furcellatus 
Lam., and cited specimens of the latter from 
Central and South America as well as from Ha- 
waii. 
I have grown the species in question for 
several years and I know its morphology and 
growth habits well. I have also obtained and 
observed H. furcellatus Lam. and find the two 
populations very similar. It is easy to see how 
Hochreutiner arrived at his conclusion. How- 
ever, after examining them minutely I feel that 
their differences warrant the classification of 
them as distinct species. 
Table 1 shows several important distinguish- 
ing characteristics. 
Skottsberg (1926) reviewed Hochreutiner ’s 
revision and concluded that the latter’s proposed 
close proximity of H. Y oungianus and H. fur- 
cellatus was an improbable one. 
A contradiction regarding locality might also 
be thought to exist when comparing a state- 
ment of Hillebrand’s found in small print fol- 
lowing his description of H. Y oungianus ("In 
marshes and abandoned taro patches here and 
there on all the islands. . . .”) with a statement 
of Mrs. Sinclair’s (1885) that the species 
. . . was once a common flower in nearly all 
valleys and sheltered places; seeming to flourish 
equally well on both the leeward and windward 
sides of the islands. Now cattle and cultivation 
have almost exterminated the plant on the dry 
lee-side, but it is still frequently met with on 
the windward side; where, owing to the more 
luxuriant vegetation, many plants, which have 
disappeared from the leeward side, are still 
found. The Hauhele {sic'] was once so plentiful 
in many parts that the aho’ (thatching sticks) of 
the houses were made of the stems, and any- 
one who knows what a great quantity of 'aho’ a 
single, old-fashioned house required, will readily 
see how abundant the plant must have been. 
Fig. 1 . Hibiscus Y oungianus Gaud, ex H. & A. Kawainui Swamp, Kailua, Oahu. Roe no. 205. Half scale. 
a, Cross section of ovary, XI \b, staminal column, X L 
