— m — 



Pteridophyta 1 ) 



by H. Christ — Basel. 



Ferns from Siam are rather scarce in the collections, and this 

 Empire, between well known Burma and pretty well explored 

 Tonkin, forms a blanc, which the Danish Expedition has diminished 

 in a very satisfactory manner. 



On account of the small size of Koh Chang and its short di- 

 stance from the mainland, I think we are right in supposing that 

 the present fern-collection will be only a scanty extract ot the flora 

 of the Continent. Notwithstanding, it characterizes very well this 

 region as a transitory one between the Malayan Peninsula and the 

 most Eastern shores of Asia, in other terms: between the Monsoon 

 flora and the Chinese flora. 



On the whole the ferns of Koh Chang belong decidedly to the 

 former, but some species will clearly show the influence of the 

 latter: Alsophila podophylla, known from Hongkong, S. W. China 

 and Tonkin (Père Bon), Brainea insignis, from S. W. China (Henry), 

 Tonkin (Billet) to Assam are of this number. 



As to rarities or endemic forms in an island of so small a size 

 we might not expect many surprises. Nevertheless, the fern-flora of 

 Koh Chang is by no means a poor one. Among the usual Malayan 

 species we meet with Adiantum Bonii Chr., a native plant of Tonkin 

 (Père Bon) and closely allied to A. Levingei Baker, Summary 27, 

 of Sikkim, to A. Celebicum Chr., Ann. Buitenzorg XV, 1, of Celebes 

 and to A. Hosei Bak. Journ. bot., 1888, 324, of Borneo; a subspecies 

 of Gleichenia linearis Burm.: G. subpectinata n. sp., a new Tricho- 

 manes Siamense, of the group of T. rigidum Sw., the curious var. 

 undulata (Wall.) of Gymnopieris costata (Wall.) rather rare in 

 India, and var. Schmidtii of the common Acroatichum aureurn L. 

 with very cuspidated leaves. 



1 ) Selaginella determined by Professor G. Hieronymus, Berlin. 



