APB. 1912.] ^_ HAYATA.-SOME PLAA^TS FROM FORMOSA. 107 



hunging straight, while those of Vittaria ate quite flat, dull- 

 greenish above, pale-yellowish beneath, and hang droopingly. 

 Besides, the structure of their sori is so widely different, that 

 it needs hardly pointing out. The two, very similar in appear- 

 ance, but widely different in character, exist nearly side by side 

 in this region on an altitude of nearly 7.000 ft. D. Nakan close- 

 ly resembles the Japanese D. Miyoshianum in having linear sori 

 between the costa and the margins, flattened costa, slightly 

 inflexed margins, very long linear fronds and comparatively 

 short stipes. But it differs principally from the other by the 

 soriferous furrows which are slightly widened inside, so as to 

 make an urceolate pore in transversal section ; the much more 

 flattened costas on the lower surface of the fronds, which costas 

 are very slightly furrowed on the middle, so as to form divari- 

 cate arms in transversal section ; the much more recurved 

 margms; and the narrower furrows on the upper surface of the 

 fronds ; and in not having peculiar and remarkable thickening 

 of epidermal tissue on the costas of the upper surface. The 

 margins of the Formosan fern are, in section, like drooping 

 arms, while there of the other are more divaricate, in section"^ 

 spreading nearly horizontally. The soriferous furrows of the 

 latter are, in section, campanulate, but not urceolate ; the costa 

 on the upper surface has a peculiar and remarkable thickening 

 in the epidermal tissue. What is more interesting to notice, the 

 new one is nearer to Vittana, to which the present genus has a 

 close affinity, than the other. The present fern has no peltate 

 paraphysis and the soriferous furrows are much wider,— charac- 

 ters which would have united Drymoixnium and Vittaria into 

 one genus, but for the articulated stipes which make the amal- 

 gamation impossible. The following description is drawn from 

 the best example of the species collected by myself in the forests 

 of Mts, Arisan. 



Drymotaenium Nakaii Hayata, Sur une espece nouvelle de 

 Fougere de genre Drymotaenium de Formose, Bull. Societ. Bot. 

 Franc. (1911) pp. 563-566. PI. XIX. Rhizoma ut videtur supra 

 truncos repens, teres, gracile, 1 mm. in diametro sectionis, subtus 

 radices nigras filiformes numerosissimas ramosas emittens, supra 



