214 LASTBEA RIGIDA. 



Lastrea — ? Bigida — Rigid. 



The Rigid Shield Fern, or, as Mr. Moore has called it, the 

 Rigid Buclilcr Fern, is a pretty hardy deciduous British 

 species, easily grown both in a Fernery and under pot-culture. 



A local species, confined to the limestone mountains of "West- 

 morland, Lancaster, and York, and even in these localities 

 extending over a small area. In Ireland it has been found 

 in the county of Louth. In England Mr. Moore remarks 

 that it ranges between twelve and fifteen hundred feet above 

 the sea-level. 



It is a native of France, Switzerland, Sardinia, Sicily, Calabria, 

 Germany, Dalmatia, Croatia, Hungary, Morea, Siberia, Asia 

 Minor, California, and Massachusetts ; in the two latter countries 

 it attains a smaller size. 



The caudex is thick, tufted, scaly, and decumbent. Stipes 

 short, densely scaly. Rachis scaly. Venation branched. Fronds 

 bipinnate, triangularly elongate. Pinnae alternate, triangular in 

 form. Pinnules oblong, base truncate, apex obtuse. Length 

 from one to two feet; colour dull green, paler on the under 

 side. Numerous minute glands are scattered over the frond, 

 giving it a somewhat glaucous appearance. 



There are no permanent varieties of this species. 



The Lastrea rigida is readily recognised from L. JiUx-mas, 

 by its more rigid habit, and by the dusty look of its fronds 

 and their smaller size. 



For plants of L. rigida I am indebted to Mr. Joseph Side- 

 botham, of Manchester; Mr. Wraight, of Newlands; Mr. Clapham, 

 of Scarbro'; and the late Mr. Clarke, gardener to INIr. Wilkin- 

 son Dent, of Flass House, Crosby Ravensworth, Westmorland; 

 to Mr. Clarke my obligations are more particularly due for 

 an extensive series of specimens of this species, gathered in his 

 neighbourhood. 



The Rev. G. Finder found this Fern in great profusion 

 growing in the crevices of rocks along the whole of the great 

 scar limestone district between Arnside and Ingleborough, being 

 most abundant on Hutton Roof Crags and Farlton Knot. It 

 is usually much damaged by wind, and also by sheep. The 

 sheep seem fond of eating its fronds. 



