134 IIISTOIIY OF BRITISH FEENS. 



Asplenium Enta-muraria, Linnwus. 



The Rue-leaved Spleenwort, or Wall Rue. 

 (Plate XIII. fig. 1.) 



A very diminutive, and not very attractive Fern, occur- 

 ring abundantly on old walls, often in such situations 

 little more than an inch high. It grows in tufts, insinu- 

 ating its wiry roots, as is the case with all the mural 

 species, into the crevices and joints of the masonry, and is 

 not easily removed from such places in a condition suitable 

 for planting. 



The fronds are numerous, of a glaucous-green, varying 

 between one and six inches long, with a stipes about half 

 the entire length, the leafy part usually triangular in out- 

 line, and bipinnate. The pinnae are alternate, with rhom- 

 boidal, or roundish-ovate, or obovate pinnules, sometimes 

 wedge-shaped, with the apex abruptly cut off. The more 

 luxuriant fronds are once more divided, so as to become 

 almost tripinnate, the pinnules being deeply pinnatifid, 

 and the lobes formed like the ordinary pinnules. When 

 the plants are quite young, the fronds are simple and 

 roundish kidney-shaped. At a later sto.ge of development 

 they are occasionally only once pinnate, with pinnatifid 



