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PACIFIC SCIENCE, VoL VI, October, 1952 
at base (lateral nerves 5 or 6 per side), doubly 
serrate at margins, green above, glabrous 
beneath, shallowly 5-lobed, the middle lobe 
shortly ovate, acuminate or caudate-acuminate 
at apex, the lateral lobes smaller, acute to 
obtusish at apex; petioles 5-7 cm. long. 
Fruits yellowish brown, small, racemose; nut- 
lets subellipsoidal, about 6 mm. long and 
4 mm. broad; wings with nutlets 1.8-2. 3 cm. 
long, 6-7 mm. broad, divaricate at 90-110°; 
pedicels 7-10 mm. long, slender, glabrous. 
Endemic to Eormosa, in forests at high 
altitudes of 1,800-2,200 meters, central ranges. 
Formosa: Mt. Taihei, Taihoku-syu, S. 
Suzuki 247 (NTU); New Paisienshan, H. 
Keng, Nov. 5, 1950 (NTU, US). 
8. Acer serrulatum Hay. (1911: 70). 
Acer oliverianum Pax var. nakaharai Hay. 
(1911: 68); Koidz. (1911^: 33, pi. 20); 
Kanehira (1936: 405, fig. 362). 
Acer oliverianum Pax var. nakaharai Hay. 
f. longistaminum Hay. (1911: 69). 
Acer oliverianum Pax var. microcarpum Hay. 
(1911: 69). 
Acer oliverianum Pax var. nakaharai subvar. 
for?nosanum Koidz. (1911^: 33, fig. 1). 
A tree up to 20 m. high; branchlets reddish, 
glabrous. Leaves rounded-cordate to broadly 
orbicular, about 7-7.5 cm. long and 9-10 cm. 
broad, glabrous on both surfaces, cordate at 
base, the nerves about 5 per side, the veinlets 
finely reticulate, distinct on both surfaces, 
palmately 5-lobed, the lobes more or less 
equal or the lower smaller, triangular- 
lanceolate to triangular-ovate, irregularly or 
duplicately crenate-serrate, the terminal lobe 
about 5-7.5 cm. long and 1.5-2 cm. broad; 
petioles 2-2.5 cm. long, glabrous. Flowers 
in terminal cymose inflorescences; peduncles 
3-5 cm. long, glabrous; pedicels to 6 mm. 
long; sepals 5, rounded-oblong, 2 mm. long, 
hirsute toward the apex on both surfaces, the 
margins tomentose-ciliate; petals 5, yellow, 
rounded, 1.25 mm. long, obscurely denti- 
culate to subentire at margins; stamens 5-7, 
the filaments 1 mm. long, the anthers oblong, 
1 mm. long; ovary 0.6 mm. long, hirsute; 
styles 2, connate, about 2 mm. long; disc 
thick, 5-7-lobed, the lobes rounded. Nutlets 
ellipsoid-oblong, about 14 mm. long; wings 
obovate, with nutlets 2.5 cm. long, divaricate 
at 90-120°. 
Endemic to Formosa, common in forests 
at altitudes of 1,000-2,000 meters throughout 
the island. 
Formosa: Sozan, E. H. Wilson 10786 (US); 
Taihoku, E. H. Wilson 10129 (US); Mt. Mor- 
rison, H. H. Bartlett 6297 (US) ; Bunzan-gun, 
Taihoku-syu, T. Suzuki 18390 (NTU); be- 
tween Pianan and Sikayo, U. ISiasamune 1082 
(NTU), Kiriyama and Tiponzae, S. Suzuki 
11019 (NTU). 
This species is the largest tree of the genus 
on the island, widely distributed and very 
common in forests at altitudes of about 
1,000-2,000 meters. Although some variations 
in the leaves are found, the plants from 
different localities clearly represent a single 
species. Kanehira’s combination of A. serru- 
latum and A. oliverianum var. nakaharai is 
thus followed. The type of A. serrulatum is 
a sterile specimen, and for this reason. Fang 
(1939: 87), who has examined .the type, could 
not ascertain the identity of the species. Ear- 
lier, however, Koidzumi, who also had access 
to the type, had already listed Hayata’s name 
in the synonymy of A. oliverianum var. naka- 
harai Hay. 
This species is here considered as distinct 
from A. oliverianum of western China. It 
differs from the latter in the more deeply 
serrate leaves, with crenate instead of sharply 
appressed serrations. The sepals are densely 
hirsute and the stamens are shorter than in 
A. oliverianum. Furthermore, A. serrulatum 
has the fruit- wings divaricate at about 120°, 
whereas in A. oliverianum the fruit- wings are 
spreading horizontally. 
In A. oliverianum^ Koidzumi described an- 
other subvariety, A. oliverianum var. nakaharai 
subvar. trilohum Koidz., with 3-lobed leaves. 
This, as noted above, is now known as A. 
