THE RUE-LEAVED SPLEENWORT, 



OR WALL RUE. 

 Asplenium Suta-muraria. Lnrcratrs. 



This is a very diminutive Fern, growing, as its name 

 implies, upon old walls, and very common on the lime- 

 stone rocks, like the Rue in general appearance ; some- 

 times not above an inch high, seldom in the most 

 favourable situations reaching to the height of six 

 inches. Its fronds are numerous, of bloom-covered 

 (glaucous) green, usually triangular in outline, bip in- 

 nate, and with a stipes about half the entire length of 

 the plant. The pinnse are alternate, with rhomboidal, 

 or roundish-ovate, or obovate pinnules, the base wedge- 

 shaped, tapering into a more or less distinct petiole, 

 the apex rounded or truncate, or sometimes acutely 

 prolonged, always toothed with 

 small or nearly equal teeth. The 

 more luxuriant fronds become 

 almost tri-pinnate, the pinnules 

 deeply pinnatifid, and the lobes 

 formed like the ordinary pin- 

 nules. When the plants are 

 quite young, the fronds are 

 simple and roundish kidney-shaped. At a later stage 

 they are occasionally only once pinnate, with pinnatifid 

 pinnae. The upper margins of the pinnules are irreg- 



