Acer in Formosa — Li 
291 
white, emarginate, 3.5-4 mm. long; stamens 
8, shorter than the sepals; ovary glabrous; 
pedicels 5-6 mm. long, slender, glabrous. 
Fruit yellowish brown; nutlets about 5 mm. 
across; wings falcate, with nutlets 2-2.2 cm. 
long, 8-12 mm. broad, spreading at obtuse 
angles; pedicels 6-7 mm. long. 
Endemic to Formosa, in forests of high 
mountains in the central range, from 2,000 
to 2,500 meters. 
Formosa: Mt. Taipinshan, H. Keng 1224 
(NTU, US); Arisan, E. H. Wilson 9643 (US), 
10830 (US). 
Fang (loc. cit.) maintains A. morrisonense 
and A. taiton-montanum as distinct species, 
but Kanehira reduces both to the synonymy 
of A. kawakamit. A. taiton-montanum is here 
treated as representing a variety of the latter 
species. A. ovatifolium Koidz. is suggested by 
Fang (1939: 181) as '‘probably identical with 
Acer kawakamii Koidzumi,” and I think this 
is where it should be referred. As undivided 
and lobed leaves are often found on the same 
plant, this character alone is apparently not 
constant enough for specific distinction. 
5a. Acer kawakamii Koidz. var. taitonmonta- 
num (Hay.) comb. nov. 
Acer taiton-montanum Hay. (1913: 67). 
Leaves chartaceous, triangular-ovate, 5-7 
cm. long, 4-5 cm. broad, the margins doubly 
serrate, undivided or shallowly 3- or 5 -lobed. 
Fruiting racemes to 4 cm. long; nutlets slight- 
ly concave, about 1 cm. long and 5 mm. 
broad; wings with nutlets 2.5-3 cm. long, 
about 8 mm. broad, spreading at right angles; 
pedicels 6-7 cm. long, glabrous. 
Endemic to Taiton Mountains, northern 
Formosa, near sulfur hot springs at about 
650 meters altitude. 
Formosa: Sozan, Taihoku-syu, T. Tanaka 
& Y. Shimada 11006 (US), E. H. Wilson 11229 
(US), N. Eukuyama 8010 (NTU). 
Acer taiton-montanum is treated as a synonym 
of A. kawakamii by Kanehira and as a distinct 
species by Fang. It is very close to A. 
kawakamii, differing only in the larger fruit. 
The leaves also vary from undivided to 3- 
or rarely 5 -lobed. The typical variety of A. 
kawakamii occurs in the high central moun- 
tains from 2,000 to 3,000 meters, whereas 
this variety is confined to the Taiton Moun- 
tains in northern Formosa at an altitude of 
about 650 meters, near sulfur hot springs. 
This is an interesting case of ecological dif- 
ferentiation. There are similar examples in 
other plants occurring in these two localities. 
6. Acer tutcheri Duthie var. shamadai Hay. 
(1911: 70); Kanehira (1936: 405). 
Acer oliverianum subvar. trilohatum Koidz. 
(1911^: 34, fig. 2). 
A deciduous tree. Leaves broadly rhom- 
boid, about 15 cm. long and 7 cm. broad, 
3-lobed, rounded at base, distinctly 3-nerved, 
serrulate at margins, subentire toward base, 
the lobes similar in size or the basal ones 
slightly smaller, the terminal lobe broadly 
triangular, about 2.5 cm. long and 3 cm. 
broad; petioles about 4 cm. long. Infructes- 
cence cymose, terminal, about 6 cm. broad 
and 7 cm. long including the peduncles of 
2-3 cm.; fruit glabrous, the nutlets ovoid, 
about 4.5 mm. long; wings with nutlets about 
1.5 cm. long and 6 mm. broad, divaricate at 
about 40°. 
Endemic to Formosa, central mountains, 
in forests. No specimen seen. 
The typical variety of A. tutcheri is confined 
to Kwangtung and Kwangsi, The Formosan 
plant, as described by Hayata, appears to be 
very close to it except in the smaller fruit 
and much less divaricate wings. This variety 
is not treated in Fang’s revision. 
7. Acer rubescens Hay. (1911: 66); Koidz. 
(1911^: 21, pi. 11); Kanehira (1936: 405, 
fig. 363). 
A deciduous tree, 10-20 m. high; branch- 
lets glabrous. Leaves chartaceous, roundish- 
ovate in outline, 6-10 cm. long, 5-8 cm. 
broad, truncate or subcordate and 5 -nerved 
