HISTOET OP INTEODUCTION OF EXOTIC FEENS. 30 



Hemionites vestita, but described as having free veins. 

 Whatever difference then may actually be in the 

 character of the venation of these three species there 

 can be no doubt but that they are closely alhed and 

 constitute a very natural group. , I have always 

 considered that Hemionites vestita does not well asso- 

 ciate with true Hemionites, but now, having found 

 two companions for it, I view them as forming 

 a natural genus, to which I apply the name Chrys- 

 cdium, I hope that ere long we may have the op- 

 portunity of becoming better acquainted with them ; 

 their silky appearance renders them worthy of being 

 added to our living collections. 



In the Fijis again. Ferns form a conspicuous feature 

 in the vegetation. During a visit of only six months, 

 recently paid to these islands by Dr. Seemann, for the 

 purpose of exploring them and investigating their 

 Flora, he collected specimens of about 800 species of 

 plants, a ad of these one-seventh were Ferns, very 

 few of which are yet known in our gardens. A few of 

 the desiderata are worth mentioning, particularly the 

 graceful Todea Wilhesiana, found by the collectors 

 attached to the United States' Exploring Expedition, 

 and named by Mr. Brackenridge in compliment to 

 Commodore Wilkes, who was in command of the 

 expedition. It is spoken of by Brackenridge as the 

 " Little Tree-fern," and as being not more than three 

 or four feet high ; but Seemann found it in the moun- 

 tains of Somosomoj where it grows as underwood, 

 attaining seven feet in height, and often with several 

 crowns. The stem is as slender as a walking-stick, 

 and the fronds bipinnate, and about two feet in length, 

 with the ultimate pinnules thin, but not so delicate or 



