112 HISTORY OF BRITISH FERNS. 



ones, but closely resemble those of crisfata, the fertile ones 

 having much more the appearance of those of the ta}-. 

 spimdosa, only that they are narrower, and have narrow 

 pinnae. The outline of these fertile fronds is narrow 

 lance-shapcd, the pinna) having a narrow tapering form, 

 and the pinnules being oblong-pointed, with rather deep, 

 serrated, marginal notches, the serratures terminating in a 

 fine point. The midvein of the pinnules is tortuous, 

 giving off branched lateral veins, the anterior of which 

 bears a sorus, so that these latter are placed in two regular 

 lines lengthwise on each pinna ; the sori are produced from 

 the base to the apex of the frond, and are covered by even- 

 margined, kidney-shaped scales or indusia. The barren 

 fronds are broader, usually shorter, less erect, and their 

 pinnules are of a broader, blunter form, and more closely 

 placed, than those which are fertile. Sometimes after the 

 growth of the first set of fertile fronds others spring up 

 Avhicli are also fertile, but have the appearance described 

 above as peculiar to the barren ones ; these fronds being 

 undistinguishable from cultivated fronds of L. crlstata. 

 This plant is found on boggy heaths, generally in company 

 with cristata and sjnnulosa ; but it is comparatively rare. 

 The variety spiniilosa, known as the Narrow Prickly- 



