HISTORY OP INTRODUCTION OF EXOTIC FERNS. 27 



podice, including P. coniiguum and P. Emersoni, 

 wiiichj on account of their sporangia being seated in 

 a deep cyst, and protruding outwards, are referred by 

 some authors to Davallia. Two fine Tree-ferns are 

 also worthy of notice, Alsopldla crinita and Cyatkea 

 Walheri. Many of the islands of the Eastern Archi- 

 pelago likewise offer a fertile field for the fern 

 collector, being rich in species of Mymenophyllum, and 

 Trichomanes, Asplervmm, Lomaria, as well as in Tree- 

 ferns of the genera Gyathea and Alsophila. The one 

 or more Sumatran Ferns yielding the singular styptic 

 drugs brought to this country of late years under the un- 

 couth names of Penghawa, Djambi, and Pakoe Kidang, 

 .would be of interest to cultivators from their beauty, 

 and to pharmaceutists from their properties. Gibotium 

 djambicmum, Dicltsonia chrysotricha, and two other 

 species of AlsopJdla {A. lurida and tomentosa) have 

 been mentioned as the sources of these drugs ; but 

 very httle is known respecting any of them, and 

 more information is desired. Two singular and 

 peculiar Ferns widely spread throughout this region 

 are Tcenitis hlechnoides and Osmunda Javanica, which, 

 although long known in herbaria, have not yet 

 found a place in our living collections. The Moluc- 

 cas and Celebes, especially, possess large numbers ; 

 and among those in the former is the rare Gystodium 

 sorbifolium, known only from a few imperfect spe- 

 cimens from these islands, and from the island of 

 Honimoe.: Mauritius contains several which would be 

 acceptable in our gardens ; but, with such an enthu- 

 siastic explorer as Mr. Duncan in that island, it is. 

 to be hoped that they will not long be classed 

 among our desiderata. I would particularly call atten- 



