BRITISH FERNS. 



51 



The fronds make their appearance in May : at first they are 

 perfectly circinate, but after a few days the apex of each is 

 liberated, and hangs down, the frond at this period possessing 

 the bend which characterises a 

 shepherd's crook, as represented 

 in the illustration. In this state 

 it is very tender, and is generally 

 cut down by the late frosts of 

 spring ; the loss is, however, 

 quickly supplied; a second series 

 of fronds make their appearance, 

 and expanding at a more con- 

 genial time, arrive in safety at 

 maturity. The fronds are mature 

 in August, and last to the middle of 

 winter quite uninjured. They are 

 generally fertile, but plants are not 

 of unfrequent occurrence which 

 produce only barren fronds ; and 

 these are generally larger, greener, 

 and have the pinnulse more deeply 

 serrated than when fertile : the 

 fronds vary from five to ten or 

 more in number, their position is 

 nearly erect, or, perhaps, some- 

 what slanting, and radiating from 

 a common centre. The length of 

 the fronds averages between two 

 and three feet, and the rachis is 

 naked nearly one-third of its 

 length, and very chaffy. 



The form of the frond is 

 lanceolate and pinnate ; the lower 

 pinnae are considerably shorter 

 than those of the middle of the 

 frond, but never approach the 

 diminutive size of those of Oreo- 

 pteris : the pinnulae are nearly 



linear, but acute at the apex ; they are regularly pinnate ; the 

 pinnulae are obtuse, somewhat pinnate at the extremities, and 

 serrated at their margins. 



