26 JOURNAL OF THE ARNOLD ARBORETUM [vol. ii 



north it is 12.2 miles broad. The circumference of the island is about 708 

 miles, and the total area is about 13,908 square miles, bein^^ about the same 

 size as Kyushu, the southern island of Japan. Formosa is very mountain- 

 ous, with a central axis stretching from north to south and situated well 

 toward the east side. The central range is composed of palaeozoic rocks, 

 chiefly clay slates and its average height is about 3000 m. Several peaks 

 are over 3(500 m. and the highest, Mt. Morrison, situated on the Tropic 

 of Cancer, is 3985 m. high. The north is largely volcanic while the extreme 

 south is of coral formation. The east coast is for the most part bold, 

 rugged, and without safe anchorage. From Pinan to Karenko stretches a 

 coastal range, largely volcanic, and not more than 1200 m. high. Between 

 this coastal range and, the foothills of the main axis is a narrow valley 

 which constitutes the only agricultural area of this region. West of 

 Karenko and stretching southward to Pinan is an outcropj)ing of limestone 

 of no great thickness. From Karenko northward, hard, crystalline schis- 

 tose rocks prevail and these form the famous seaclifTs of northeast Formosa. 

 These cliffs seen from the sea appear to be vertical walls of rock fullv 2G0O m. 

 tall. 



The west coast is separated from China by the Formosa Channel, whicli 

 is nowhere more than 100 fathoms deep. The short rivers that flow from 



the mountains bring down annually enormous quantities of detritus, 

 spreading it out over the alluvial plains whicli are constantly increasing 

 in size. Many of the foothills abutting on the plain are worn into ter- 

 raced flats with vertical faces. About 80 miles south of Taihoku an east 

 and west range of hills extends to the sea and exercises a strong influence on 

 the climate. Oaa ing to the influence of the Japan current which flows up 

 the cast coast the mean temperature is higher and the rainfall more copious 

 than in the corresponding latitudes on the continent. The rainfall varies 

 considerably in diff'crent parts of the island. At Keelung in the north it 

 averages al>out 130 inches, while at Taihoku. only 17.8 miles south and one 

 hour*^ journey by train, it is about 76 inches. At Takao in Ihe south it is 

 about 70 inches, and at Koshun about 84 inches. Thanks to the range of 

 hills wliich bisect the island the wet and dry seasons of the northern and 

 southern parts of Formosa alternate. 



The rich i)lains on the west coast suj)port a large agricultural population. 

 Rice, of which two crops are harvested each year, is the staple, while in 



recent years sugar-cane has been grown in enormous quantities. The allu- 

 vial areas have nearly all been brought under cultivation. In the north the 

 foothills are also largely given over to agriculture, and the Camj)hor-tree 

 in great quantities has been planted. In the central parts of the island are 

 several ui)land valleys, really old lake beds, and these loo are under croi)s. 

 Of the many lakes which at one time existed in this region only one, Lake 

 Candidius, remains. In the north and centre the Tea-j)lant is grown in 

 quantity and the " Oolong Teas " of Formosa are famous. In places 

 Citronella-grass is cultivated for its oil, while Pananas, PcLlc-nut Palm and 

 the Longan-trce are features round homesteads at low altitudes. Where 



