36 ASPLENIUM 



WALL RUE; RUE SPLEENWORT: 



Asplenium Ruta-muraria. 



Fronds seldom more than 5 inches high, grow- 

 ing in tufts, twice or three times pinnate at the 

 base, with stalked' pinnae and pinnules; pinnae 

 usually alternate; pinnules wedge-shaped, with 

 outer margin slightly toothed; rachis and stipe 

 green. 



Nearly every frond fertile, 2 to 4 fruit dots 

 borne on each pinnule. 



Found on limestone cliffs from Vermont to On- 

 tario, Michigan and southward. 



