or THE EASTERN BORDERS. 



307 



The remains of this delicate Fern are very beautiful ; they appear 

 like the work of a tasteful artist who had impressed their elegant 

 forms in burnished copper on a deep red metallic ground. It re- 

 sembles a living Hymenophyllum ; but a nearer analogue is a species 

 of Davallia from the West Indies which we have seen in the col- 

 lection of Mr. Morris. Several of the species of Sphenopteris, with 

 narrow segments, may hereafter be united, as the slight differences 

 among them may have been caused by difference of situation and 

 age. Our species is nearest to S. elegans of Brongn. ; but the rachis 

 is more winged, the pinnse more slender, and the termination of the 

 lobes less obtuse than in that species. We find also, from specimens 

 recently obtained, that one central vein passes into each lobe or ulti- 

 mate segment. We have named it after Dr. Johnston, as a mark of 

 respect to a distinguished naturalist, whose writings and labours have 

 added much to our knowledge of the natural history of our country. 



Locality. Budle, in shale. 



Fig. 2. 



Fig. 2. A fragment of a pinna, the pinnules somewhat distorted, 

 the rachis having on each side of a central ridge a series of puncta- 

 tions. 



Fig. 2. A. Magnified view of the rachis. We have another spe- 

 cimen showing the same kind of punctations ; they may have been 

 caused by the shrinking of the tissues, when the plant was in course 

 of fossilization. 



X 2 



