1920] WILSON, PHYTOGEOGRAPIirCAL SKETCH OF FORMOSA 37 



20 to 30 ft. tall. Among broad-leaf trees Trochodendron aralioides S. & Z. 

 is peculiar to this belt and round Ari-san is particularly abundant gro\ving 

 with the Taivvania and the two species of Chamaecyparis. It is a much 

 branched, wide-spreading tree with a short trunk often 20 ft. in girth and 

 from 60 to 80 ft. in height. This tree has a very wide distribution north- 

 ward through Liukiu, Yaku-shima, Kyushu and Hondo to the Nikko region, 

 and the finest trees that I have seen grow in the Cryptomeria-forests on 



Yaku-shima. 



The various Fagaceae of the lower mountains are also present and domi- 



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noblest of Formosan Oaks. It grows a hundred or more feet tall and has a 

 broad-topped crown and a very thick trunk clothed with gray bark which 

 flakes off in thick plates. This species worthily commemorates one of the 

 pioneer Japanese explorers and botanical collectors in Formosa. Lauraceae 

 decrease rapidly in numbers above 2500 m. altitude, but on the upper parts 

 of Ari-san grow scattered trees of Sassafras randaiense Rehd., a recently 

 recognized third member of this Interesting genus. Among smaller trees 

 Adinandra lasiostyla Hay., several species of Symplocos including S. cno- 

 botryaefolia Hay. with lamellate pith, Gilibertia pellucidopunctata liny. 

 with polymorphous leaves, Otherodendron illiciifolium Hay., Photinia ser- 

 rulata Lindl., and various species of Thea, Ilex and Osmanthus are note- 

 worthy. Of large shrubs or small trees with conspicuous flowers mention 

 may be made of Hydrangea KawaJcamii Hay. with huge deciduous leaves 

 and broad flat corymbs of pink and blue flowers, Viburnum melanophyllum 

 Hay. which is related to the Japanese V.furcatum Bl., Photinia niitakaya- 

 mensis Hay., which is really a Stranvaesia, and has white flowers in corymbs 

 and scarlet fruit, Prinsepia scandens Hay., which is not scandcnt, and has 

 white, fragrant flowers and arching, green branchlets, Mahonia lomariifoha 

 Takeda, Berberis Kawakamii Hay., Rhododendron Morii Hay., R. Tanakai 

 Hay., R. formosanum Hemsl. and others. Rubi in many species abound, 

 and in open, grass-clad regions beyond Ari-san Rhododendron rubropilosum 

 Hav. is common and so too is the lovely Pieris taiwanensis Hay. Among 



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Evonymus Spracjuei Hay., Kadsura japonica S. & Z., Actinidia chinensis 

 Planch, and other species, Iledera himalaica Tobl., Clematis Morii Hay. 

 and others, and species of Smilax and Ficus demand notice. The forest- 

 bed in all but the most intensely shaded places is choked with Arundinaria 

 niitakayamensis Hay. and A. oiwakensis Hay. These graceful Bamboos 

 with their feathery culms grow from 6 to 10 ft. tall, and form Impenetrable 

 jungles and ultimately crowd out all other undergrowth. Epiphytic plants 

 are plentiful including such shrubs as Rhododendron Kaivakamii Hay., 

 Vaccimumemarginatumllay., V.caudatifolium Hay., Gaulhcria Cumingi- 

 ana Vidal, Pachycentria formosana Hay. and the pinnate-leaved Penta- 

 panax castanopsisicola Hay. Different species of Loranthus are common 



