278 



Genus Eupteris. 

 Roots fibrous. 



Rhizoma subterranean, horizontal, rapidly extending. 

 Frond single, rising perpendicularly from the rhizoma at longer or 

 shorter intervals : its stipes erect ; its vernation bent, not cir- 

 cinate ; its texture subcoriaceous ; its division compound ; its 

 ultimate divisiofis sessile, with distinct midvein and many di- 

 chotomously branched lateral veins, all of which are united to a 

 marginal vein. 

 Fructijlcation. The marginal vein of the ultimate divisions serves as 

 a receptacle for the capsules, these being attached almost 

 throughout its length in a continuous linear series, which is co- 

 vered by the bleached fimbriate superior epidermis : involucre 

 linear, its free margin fimbriate, its fixed margin attached to 

 the marginal vein beneath the capsules. 

 Many years have elapsed since I ventured to express an opinion 

 that genera were for the most part human inventions, designed to ac- 

 commodate or promote the views of their author, and by no means 

 positive indications of natural grouping. Up to the present time I 

 have seen no reason to alter or modify the opinion then expressed : 

 still, when the work of subdivision has been commenced, when a 

 striking species has been abstracted here and there fromalai'ge group, 

 and a number of " common and less interesting forms "* allowed to 

 remain under the original generic title, then the constitution of the 

 genus becomes wholly changed, and its author could not recognise his 

 own handywork in the impoverished group as subsequently restricted. 

 This is the case with Pteris, and here I should observe, that in ven- 

 turing on my present task, it is not the Pteris of Linneus of which I 

 treat, but that fractional part thereof — the Pteris of John Smith, or 

 the Allosori aquilini of Presl. 



I will now endeavour to explain somewhat more at large the pecu- 

 liarities of the new genus which I propose to establish. 



The rhizoma, fig. 1, a, is entirely subterranean, nearly cylindrical, 

 and usually about the size of a goose-quill ; it is remarkably succulent, 

 and is clothed with a dark brown velvety coating : it extends very 

 rapidly in a horizontal direction. 



The fronds rise perpendicularly from the rhizoma at unequal inter- 

 vals : until they nearly reach the surface of the ground the stipes only 

 is discernible, the apex being rounded and disjjlaying no trace what- 



* I quote the fashionable botanical ])hrascology. 



